Nuclear Protein Expression Research Articles

Pnn deficiency alters expressions of calcium handling proteins and impairs nuclear envelope structure in cardiomyocytes

Abstract Pnn is a multi-functional protein playing roles in the regulation of gene transcription, mRNA alternative splicing, as well as cell-cell connection. Previous studies suggested an association between Pnn genetic defects and arrhythmogenic right ventricular cardiomyopathy (ARVC) in human. In this study, we applied an inducible cardiomyocyte-specific Pnn depletion mouse model (Myh6-CreERT2, Pnnflox/flox) to determine the impact of loss of Pnn on cardiac structure and function in mice. Six weeks after inducing Pnn gene disruption, electrocardiographic abnormalities, ventricular dilatation, and reduced left ventricular ejection fraction (LVEF) were observed in mice with loss of Pnn in cardiomyocytes. Histopathological examinations showed that the proliferation of cardiac fibroblasts and expression of α-smooth muscle actin were increased with Pnn depletion, while the cell-cell connection between cardiomyocytes were impaired. In addition to impaired intercalated discs, loss of Pnn also altered the distribution and expression of nuclear envelope proteins and the linker of nucleoskeleton and cytoskeleton (LINC) complex proteins, such as nuclear lamins, Emerin, and SUNs, in cardiomyocytes. Microarray analysis as well as subsequent RT-PCR and Western blots also indicated that loss of Pnn regulated myocardial expressions of genes responsible for calcium handling, such as RYR2, Atp2a2, Slc8a1, and Kcnj3. Furthermore, infiltrations of macrophages and neutrophiles were observed in the myocardium with Pnn depletion, while expression levels of oxidative stress-associated proteins were also significantly regulated by Pnn depletion. In conclusion, Pnn plays an essential role in the maintenance of intercalated disc integrity and nuclear envelope structure of cardiomyocytes, while cardiomyocyte-specific loss of Pnn impairs the calcium handling and leads to arrhythmogenic dilated cardiomyopathy in mice.Cardiac MRI of mice with Pnn depletionMyocardial expression of SUN2 and Emerin

The decrease in Rad51 and DNA ligase IV nuclear protein expression in Msh2 knockdown HC11 cells induced the low CRISPR/Cas9-mediated knock-in efficiency at the β-casein gene locus.

Successful gene editing technology is crucial in molecular biology and related fields. An essential part of an efficient knock-in system is increasing homologous recombination (HR) efficiency in the double-strand break (DSB) repair pathways. Interestingly, HR is closely related to the DNA mismatch repair (MMR) pathway, whereby MMR-related gene Msh2 recognizes a mismatch of nucleotides in recombinant intermediates or gene conversion formed during HR. This study aimed to investigate how the knockdown of Msh2 affects HR-mediated knock-in efficiency at the mouse β-casein locus. Therefore, we investigated the effect of inhibiting Msh2 expression on the expression of the HR-related gene Rad51 and the key enzyme DNA ligase IV involved in non-homologous end joining (NHEJ). The knock-in vector targeting the mouse β-casein gene locus, programmed guide RNA, and Msh2 siRNA expression vector were co-transfected in HC11 cells, or only the Msh2 siRNA expression vector was transfected. Knock-in efficiency was confirmed by polymerase chain reaction (PCR). The mRNA and protein expression of Msh2, HR-related gene Rad51, and NHEJ-related gene DNA ligase IV were evaluated by quantitative reverse transcription PCR (RT-qPCR) and Western blot analysis. The knock-in vector efficiency at the mouse β-casein gene locus significantly decreased upon Msh2 knockdown in HC11 mouse mammary epithelial cells (HC11 cell). Additionally, the knockdown of the DNA MMR-related gene Msh2 protein significantly downregulated the nuclear protein expression of the HR-related Rad51 and NHEJ-related DNA ligase IV genes. The decreased Msh2 protein expression in the nucleus downregulated the Rad51 and ligase IV protein expressions. Consequently, reduced Rad51 expression results in decreased knock-in efficiency.

CRISPR associated enzymes are mislocalized to the cytoplasm in iPSC-derived neurons resulting in KRAB-specific degradation.

The use of CRISPR-associated enzymes in iPSC-derived neurons for precise gene targeting and high-throughput gene perturbation screens offers great potential but presents unique challenges compared to dividing cell lines. CRISPRi screens in iPSC-derived neurons and glia have already been successful in relating gene function to neurological phenotypes; however, loss of dCas9-KRAB expression after differentiation has been observed by many labs and has been largely ascribed to transgene silencing after differentiation. Here, we investigated the expression levels of different CRISPR enzymes in iPSC and Ngn2-derived neurons using piggybac delivery. We found that the commonly used dCas9-KRAB (using the KOX1 domain) displayed dramatic reduction in protein expression levels following neuronal differentiation, yet surprisingly, nCas9 constructs retained comparable protein expression between iPSCs and neurons. We further found that CRISPR constructs, primarily relying on the SV40 Nuclear Localization Signal (NLS), fail to efficiently localize to the nuclei of neurons, despite having robust nuclear levels in iPSCs, leading to KRAB-specific cytoplasmic degradation. By adding a neuronal-specific NLS, we were able to correct neuronal nuclear localization and protein expression, confirming the contribution of mislocalization to the instability of dCas9-KRAB in neurons. As the lack of nuclear localization can have a profound impact on editing and gene perturbation efficiency, we suggest further investigation across both cultured and in-vivo postmitotic cell models.

Platelet-rich plasma ameliorates cartilage degradation in rat models of osteoarthritis via the OPG/RANKL/RANK system.

Osteoarthritis (OA) is one of the most common degenerative joint diseases in the elderly, which is featured by the degradation of articular cartilage. Recently, platelet-rich plasma (PRP) injection into the affected joint has become one biological therapy for OA treatment. The OPG/RANKL/ RANK signalling has been reported to mediate OA progression. Our study aimed to confirm whether PRP injection retards OA development through the regulation of the OPG/RANKL/RANK system. The OA rat models were induced by medial menisci resection combined with anterior cruciate ligament transection. Four weeks after surgery, OA-induced rats received intra- articular injection with 50 μL PRP once a week for 6 weeks. Rats were euthanised one week after the 6th injection. Rat knee joints were subjected to histopathological examination by haematoxylin- eosin (H&E) and safranin O staining. Osteoprotegerin (OPG), receptor activator of nuclear factor kappa B (RANK), and RANK ligand (RANKL) in the articular cartilage of rats were tested through immunofluorescence staining and western blotting. Serum interleukin-1β (IL-1β) and interleukin-6 (IL-6) levels were measured by enzyme-linked immunosorbent assay (ELISA). Matrix metalloproteinase- 13 (MMP-13), aggrecan, collagen α, IL-1β, IL-6, tumour necrosis factor-alpha (TNF-α), and nuclear factor kappa-B (NF-κB) mRNA and protein expression in rat articular cartilage were examined by real-time quantitative polymerase chain reaction (RT-qPCR) and western blotting, respectively. Intra-articular injections of PRP significantly improved the structural integrity of the articular cartilage and enhanced the synthesis of glycosaminoglycans. PRP reduced MMP-13 protein level but increased aggrecan and collagen α protein levels in articular cartilage of OA rats. OA-induced increase in serum IL-1β, IL-6, and TNF-α concentrations as well as increased MMP-13, and decreased collagen II mRNA levels were reversed by the administration of PRP. OA increased IL-1β, TNF-α, and NF-κB mRNA expression in rat articular cartilage whereas PRP administration ameliorated these changes. Moreover, in the articular tissue of OA-induced rats the increased OPG protein level was further elevated by PRP injections whereas the protein level of RANK did not change. The increase in the protein level of RANKL in OA-induced articular tissue was offset by PRP administration. PRP elevated OPG mRNA expression and the OPG/RANKL mRNA ratio, but reduced RANKL mRNA expression and the RANKL/RANK mRNA ratio in the articular tissue of OA-induced rats. PRP mitigates cartilage degradation and inflammation in experimental knee OA by regulating the OPG/RANKL/RANK signalling system.

Siwu tablet attenuates high fructose-induced glomerular podocyte senescence in rats through increasing Nup155 to promote INO80 mRNA nuclear export

Ethnopharmacological relevanceSiwu tablet (SWT), derived from a traditional Chinese medicinal formula named Siwu decoction, is widely used for blood deficiency syndrome. Siwu decoction and its derived formulas have been proven to improve renal anemia and prevent senescence. Whether SWT prevents glomerular podocyte senescence and the underlying molecular mechanism remains unknow. Aim of the studyTo elucidate the protective effect and possible mechanism of SWT on glomerular podocyte senescence. Material and methodsLiquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed to characterize components of SWT. Male Sprague-Dawley rats were given 10% fructose drinking water for 16 weeks. SWT (810 and 1620 mg/kg) was administered orally for the last 8 weeks. The assays of senescence-associated beta-galactosidase (SA-β-gal) staining, immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), and Western blot as well as enzyme linked immunosorbent assay were performed to evaluate rat glomerular podocyte senescence. The mRNA and protein levels of nucleoporin 155 (Nup155) and inositol requiring mutant 80 (INO80) in rat glomeruli were detected by qRT-PCR, Western blot and immunofluorescence. Foot processes and nuclear pore complexes (NPCs) of rat glomerular podocytes were visualized by transmission electron microscopy. ResultsOne hundred and fifty-nine components were preliminarily identified in SWT. The results of animal experiments showed that SWT decreased the activity of SA-β-gal, protein levels of p16, p21, p53 and phosphorylated histone H2AX (γ-H2AX), and mRNA levels of interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) in glomeruli of high fructose-fed rats. As expected, SWT increased renal cortex erythropoietin mRNA expression and serum erythropoietin concentration in this animal model. SWT reduced urine albumin-to-creatinine ratio and serum levels of uric acid, creatinine and blood urea nitrogen, and recovered glomerular structure injury in high fructose-fed rats. It up-regulated mRNA and protein levels of Nup155 and the number of podocyte NPCs, and subsequently reinforced mRNA nuclear export and protein expression of INO80 in rat glomeruli under high fructose stimulation. ConclusionsSWT ameliorates glomerular podocyte senescence in high fructose-fed rats possibly by increasing Nup155 to promote INO80 mRNA nuclear export.

Ozone Induces Oxidative Stress and Inflammation in Nasal Mucosa of Rats

Background: The development of the global economy has led to changes in air pollution patterns. The haze phenomenon characterized by high concentrations of particulate matter 2.5 (PM2.5) has changed to complex pollution, and photochemical pollution characterized by ozone (O3) has become increasingly prominent. Ozone pollution and its impact on human health has become an important topic that needs to be studied urgently. Objective: To investigate the effects of ozone on oxidative stress and inflammation in the nasal mucosa of a rat model. Methods: Thirty-two healthy female Sprague–Dawley rats, eight in each group, were divided into four groups using the randomized numeric table method: normal control group (NC group), normal rats with a low level of ozone inhalation exposure (NEL group, 0.5 ppm), medium ozone inhalation exposure (NEM group, 1 ppm), and high ozone inhalation exposure (NEH group, 2 ppm). The ozone inhalation exposure groups were placed in the ozone inhalation exposure system and exposed to different concentrations of ozone for 2 h each day for 6 weeks. Nasal secretion was measured, and nasal lavage and nasal mucosa were collected. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities were measured by colorimetric assay, and the nasal mucosa was analyzed by Western blot. Western blot (WB) was used to detect the expression of NF-κB p65 nuclear protein in nasal mucosa. The mRNA expression of NF-κB target genes IL-6 and IL-8 and tumor necrosis factor-α (TNF-α) was detected by real-time quantitative PCR (qRT-PCR), and the protein content of pro-inflammatory factors IL-6, IL-8, and TNF-α was detected by ELISA in serum and nasal lavage fluid. The nasal mucosa of rats was stained with hematoxylin-eosin (HE) to observe the pathological changes in the nasal mucosa. The data were analyzed by SPSS 20.0 software. Results: The amount of nasal secretion increased significantly in all groups after ozone exposure compared with that in the NC group. The MDA content of the nasal mucosa was significantly increased in the ozone-exposed group compared with the NC group, and the activity levels of SOD and GSH-Px in the nasal mucosa were lower in the ozone-exposed group than in the NC group. The mRNA expression of IL-6, IL-8, and TNF-α in the nasal mucosa of the ozone-exposed group was elevated, and the protein content of TNF-α, IL-6, and IL-8 in the nasal lavage fluid was elevated, and the content increased with the increase in ozone concentration. The expression of NF-κB p65 intracellular protein in the nasal mucosa of each ozone-exposed group was higher than that of the normal group, and the content increased with the increase in ozone concentration. Conclusions: Ozone inhalation exposure promotes oxidative stress and the release of inflammatory factors TNF-α, IL-6, and IL-8, leading to pathological damage of the nasal mucosa, the degree of which increases with increasing concentration. This pathological process may be related to the activation of the transcription factor NF-κB by ozone in the nasal mucosa of rats, which increases the expression of its target genes.

Downregulation of MIR-346 affects the expression of nuclear receptor-interacting protein 1 (NRIP-1) and estrogen receptors in follicular thyroid cancer

Downregulation of MIR-346 affects the expression of nuclear receptor-interacting protein 1 (NRIP-1) and estrogen receptors in follicular thyroid cancer

Muscle-derived IL-1β regulates EcSOD expression via the NBR1-p62-Nrf2 pathway in muscle during cancer cachexia.

Oxidative stress contributes to the loss of skeletal muscle mass and function in cancer cachexia. However, this outcome may be mitigated by an improved endogenous antioxidant defence system. Here, using the well-established oxidative stress-inducing muscle atrophy model of Lewis lung carcinoma (LLC) in 13-week-old male C57BL/6J mice, we demonstrate that extracellular superoxide dismutase (EcSOD) levels increase in the cachexia-prone extensor digitorum longus muscle. LLC transplantation significantly increased interleukin-1β (IL-1β) expression and release from extensor digitorum longus muscle fibres. Moreover, IL-1β treatment of C2C12 myotubes increased NBR1, p62 phosphorylation at Ser351, Nrf2 nuclear translocation and EcSOD protein expression. Additional studies in vivo indicated that intramuscular IL-1β injection is sufficient to stimulate EcSOD expression, which is prevented by muscle-specific knockout of p62 and Nrf2 (i.e. in p62 skmKO and Nrf2 skmKO mice, respectively). Finally, since an increase in circulating IL-1β may lead to unwanted outcomes, we demonstrate that targeting this pathway at p62 is sufficient to drive muscle EcSOD expression in an Nrf2-dependent manner. In summary, cancer cachexia increases EcSOD expression in extensor digitorum longus muscle via muscle-derived IL-1β-induced upregulation of p62 phosphorylation and Nrf2 activation. These findings provide further mechanistic evidence for the therapeutic potential of p62 and Nrf2 to mitigate cancer cachexia-induced muscle atrophy. KEY POINTS: Oxidative stress plays an important role in muscle atrophy during cancer cachexia. EcSOD, which mitigates muscle loss during oxidative stress, is upregulated in 13-week-old male C57BL/6J mice of extensor digitorum longus muscles during cancer cachexia. Using mouse and cellular models, we demonstrate that cancer cachexia promotes muscle EcSOD protein expression via muscle-derived IL-1β-dependent stimulation of the NBR1-p62-Nrf2 signalling pathway. These results provide further evidence for the potential therapeutic targeting of the NBR1-p62-Nrf2 signalling pathway downstream of IL-1β to mitigate cancer cachexia-induced muscle atrophy.

Altered expression and localization of nuclear envelope proteins in a prostate cancer cell system

BackgroundThe nuclear envelope (NE), which is composed of the outer and inner nuclear membranes, the nuclear pore complex and the nuclear lamina, regulates a plethora of cellular processes, including those that restrict cancer development (genomic stability, cell cycle regulation, and cell migration). Thus, impaired NE is functionally related to tumorigenesis, and monitoring of NE alterations is used to diagnose cancer. However, the chronology of NE changes occurring during cancer evolution and the connection between them remained to be precisely defined, due to the lack of appropriate cell models.MethodsThe expression and subcellular localization of NE proteins (lamins A/C and B1 and the inner nuclear membrane proteins emerin and β-dystroglycan [β-DG]) during prostate cancer progression were analyzed, using confocal microscopy and western blot assays, and a prostate cancer cell system comprising RWPE-1 epithelial prostate cells and several prostate cancer cell lines with different invasiveness.ResultsDeformed nuclei and the mislocalization and low expression of lamin A/C, lamin B1, and emerin became more prominent as the invasiveness of the prostate cancer lines increased. Suppression of lamin A/C expression was an early event during prostate cancer evolution, while a more extensive deregulation of NE proteins, including β-DG, occurred in metastatic prostate cells.ConclusionsThe RWPE-1 cell line-based system was found to be suitable for the correlation of NE impairment with prostate cancer invasiveness and determination of the chronology of NE alterations during prostate carcinogenesis. Further study of this cell system would help to identify biomarkers for prostate cancer prognosis and diagnosis.

Amino-truncated NOV expression and its correlation with clinicopathologic features, prognosis, metastasis, and chemoresistance in bladder cancer

ABSTRACT Nephroblastoma, an overexpressed gene (NOV) protein, plays an important role in proliferation, differentiation, angiogenesis, adhesion, invasion and tumorigenesis, but the function of amino-truncated NOV is different. This study is to investigate the role of amino-truncated NOV in the progression of bladder cancer. Using immunohistochemistry and Western blot analysis, we detected the amino-truncated NOV in bladder cancer, and statistical analysis was performed to estimate the association between the expression of amino-truncated NOV and the patient’s prognosis by SPSS 19.0. With transduction of amino-truncated NOV, we evaluated alteration for proliferation, migration, invasion and chemoresistance in bladder cancer cells, as well as some proteins related to Wnt/β-catenin pathway and epithelial–mesenchymal transition. The truncated variant of the NOV protein was located in a nucleus other than the cytoplasm and highly expressed in bladder cancer, which was also linked to higher pathological grade and positive lymph node metastasis as well as recurrence. The exact sequence of this truncated protein was confirmed, and it was a 26-kDa splicing. The truncated NOV protein found in bladder cancer was cut at the 187th amino acid of the full-length protein. It was also involved in bladder cancer progression and chemoresistance through a mechanism involving epithelial–mesenchymal transition (EMT) and the Wnt/β-catenin signaling pathway. Our findings provide experimental evidence that the nuclear NOV protein expression is a potential biomarker in the prognostic evaluation of bladder cancer and enhanced amino-truncated NOV expression is potentially important for bladder cancer cell invasion, metastasis and chemoresistance during progression.

A role for YAP/FOXM1/Nrf2 axis in oxidative stress and apoptosis of cataract induced by UVB irradiation.

This study aims to investigate the hypothesis that Yes-associated protein (YAP) significantly regulates antioxidant potential and anti-apoptosis in UVB-induced cataract by exploring the underlying molecular mechanisms. To investigate the association between YAP and cataract, various experimental techniques were employed, including cell viability assessment, Annexin V FITC/PI assay, measurement of ROS production, RT-PCR, Western blot assay, and Immunoprecipitation. UVB exposure on human lens epithelium cells (HLECs) reduced total and nuclear YAP protein expression, increased cleaved/pro-caspase 3 ratios, decreased cell viability, and elevated ROS levels compared to controls. Similar Western blot results were observed in invivo experiments involving UVB-treated mice. YAP knockdown invitro demonstrated a decrease in the protein expression of FOXM1, Nrf2, and HO-1, which correlated with the mRNA expression, accompanied by an increase in cell apoptosis, caspase 3 activation, and the release of ROS. Conversely, YAP overexpression mitigated these effects induced by UVB irradiation. Immunoprecipitation revealed a FOXM1-YAP interaction. Notably, inhibiting FOXM1 decreased Nrf2 and HO-1, activating caspase 3. Additionally, administering the ROS inhibitor N-acetyl-L-cysteine (NAC) effectively mitigated the apoptotic effects induced by oxidative stress from UVB irradiation, rescuing the protein expression levels of YAP, FOXM1, Nrf2, and HO-1. The initial findings of our study demonstrate the existence of a feedback loop involving YAP, FOXM1, Nrf2, and ROS that significantly influences the cell apoptosis in HLECs under UVB-induced oxidative stress.

Synaptic Vesicle-Related Proteins and Ubiquilin 2 in Cortical Synaptosomes Mediate Cognitive Impairment in Vascular Dementia Rats.

Synaptic dysfunction is considered the best neuropathological correlate of cognitive decline in vascular dementia (VaD). However, the alterations of synaptic proteins at the synaptosomal level in VaD remain unclear. In this study, a VaD model was established in male rats using bilateral common carotid artery occlusion (2VO). We performed a novel object recognition task to evaluate cognitive impairment. Immunohistochemistry was used to assess the expression of neuron-specific nuclear binding protein (NeuN). Brain synaptosomes were isolated and subjected to label-free proteomic analysis to quantify and identify the synaptic features of differentially expressed proteins (DEPs). Synaptic and hub protein expression was detected in synaptosomes using western blotting. We found that male rats with VaD presented impaired memory and decreased NeuN protein expression in the cortex. Synaptosome proteomic analysis revealed 604 DEPs, with 493 and 111 markedly downregulated and upregulated proteins, respectively. KEGG analysis and SynGO annotation revealed that the synaptic vesicle (SV) cycle may be a key signaling pathway in VaD. Hub protein analysis of the main nodes in the protein network identified UBQLN2 and SV-related proteins, including CLTC, SNAP91, AP2S1, CLTA, VAMP2, EPN1, UBQLN2, AP2B1, AP2A2, and AP2M1. Western blotting showed that the levels of SV2A, CLTC, AP2S1, and VAMP2 decreased in the synaptosomes of 2VO rats, while UBQLN2 expression significantly increased. Our results suggest that the disruption in the presynaptic SV cycle is a key event in male rats with VaD, which could be characterized by the aberrant SV2A expression. SV-related proteins and UBQLN2 may be essential in synaptopathy. Thus, targeting the specific molecular markers in synaptosomes may be critical for the development of mechanism-directed therapies against VaD.

YAP1 Suppression by ZDHHC7 Is Associated with Ferroptosis Resistance and Poor Prognosis in Ovarian Clear Cell Carcinoma.

Ovarian clear cell carcinoma (OCCC), which has unique clinical characteristics, arises from benign endometriotic cysts, forming an oxidative stress environment because of excess iron accumulation, and exhibits poor prognosis, particularly in advanced stages owing to resistance to conventional therapeutics. Ferroptosis is an iron-dependent form of programmed cell death induced by lipid peroxidation and controlled by Hippo signaling. We hypothesized that overcoming ferroptosis resistance is an attractive strategy because OCCC acquires oxidative stress resistance during its development and exhibits chemoresistant features indicative of ferroptosis resistance. This study aimed to determine whether OCCC is resistant to ferroptosis and clarify the mechanism underlying resistance. Unlike ovarian high-grade serous carcinoma cells, OCCC cells were exposed to oxidative stress. However, OCCC cells remained unaffected by lipid peroxidation. Cell viability assays revealed that OCCC cells exhibited resistance to the ferroptosis inducer erastin. Moreover, Samroc analysis showed that the Hippo signaling pathway was enriched in OCCC cell lines and clinical samples. Furthermore, patients with low expression of nuclear yes-associated protein 1 (YAP1) exhibited a significantly poor prognosis of OCCC. Moreover, YAP1 activation enhanced ferroptosis in OCCC cell lines. Furthermore, suppression of zinc finger DHHC-type palmitoyltransferase 7 (ZDHHC7) enhanced ferroptosis by activating YAP1 in OCCC cell lines. Mouse xenograft models demonstrated that ZDHHC7 inhibition suppressed tumor growth via YAP1 activation by erastin treatment. In conclusion, YAP1 activation regulated by ZDHHC7 enhanced ferroptosis in OCCC. Thus, overcoming ferroptosis resistance is a potential therapeutic strategy for OCCC.

Mesenchymal Stem Cell-Derived Exosomes Mitigate Acute Murine Liver Injury via Ets-1 and Heme Oxygenase-1 Up-regulation.

Mesenchymal stem cells (MSCs)-derived exosomes have been previously demonstrated to promote tissue regeneration in various animal disease models. This study investigated the protective effect of exosome treatment in carbon tetrachloride (CCl4)-induced acute liver injury and delineated possible underlying mechanism. Exosomes collected from conditioned media of previously characterized human umbilical cord-derived MSCs were intravenously administered into male CD-1 mice with CCl4-induced acute liver injury. Biochemical, histological and molecular parameters were used to evaluate the severity of liver injury. A rat hepatocyte cell line, Clone-9, was used to validate the molecular changes by exosome treatment. Exosome treatment significantly suppressed plasma levels of AST, ALT, and pro-inflammatory cytokines, including IL-6 and TNF-α, in the mice with CCl4-induced acute liver injury. Histological morphometry revealed a significant reduction in the necropoptic area in the injured livers following exosome therapy. Consistently, western blot analysis indicated marked elevations in hepatic expression of PCNA, c-Met, Ets-1, and HO-1 proteins after exosome treatment. Besides, the phosphorylation level of signaling mediator JNK was significantly increased, and that of p38 was restored by exosome therapy. Immunohistochemistry double staining confirmed nuclear Ets-1 expression and cytoplasmic localization of c-Met and HO-1 proteins. In vitro studies demonstrated that exosome treatment increased the proliferation of Clone-9 hepatocytes and protected them from CCl4-induced cytotoxicity. Kinase inhibition experiment indicated that the exosome-driven hepatoprotection might be mediated through the JNK pathway. Exosome therapy activates the JNK signaling activation pathway as well as up-regulates Ets-1 and HO-1 expression, thereby protecting hepatocytes against hepatotoxin-induced cell death.

Shenfu Injection regulates macrophage polarization via TLR4/NF-κB pathway to reduce inflammation in chronic heart failure

This study aimed to investigate the therapeutic effect of Shenfu Injection on mice with chronic heart failure(CHF) and its effect on macrophage polarization. C57BL/6J mice were randomly assigned to the normal and model groups. The CHF model was established by intraperitoneal injection of isoproterenol(ISO, 7.5 mg·kg~(-1), 28 d). The successful modeling was determined by asses-sing the cardiac function and N-terminal pro-brain natriuretic peptide(NT-proBNP). The modeled mice were randomly divided into the model group, Shenfu Injection group, and TAK-242 group, and were injected intraperitoneally with the corresponding drugs for 15 days. Cardiac function was evaluated using echocardiography. Hematoxylin-eosin(HE) staining was used to detect the pathomorphology. Enzyme-linked immunosorbent assay(ELISA) was used to detect the values of serum NT-proBNP, interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), IL-10, and arginase 1(Arg-1). Flow cytometry was applied to detect the relative content and M1/M2 polarization of cardiac macrophages. Quantitative polymerase chain reaction(qPCR) and Western blot were used to detect the changes in the Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB) pathway-related mRNA and protein expressions. Compared with the normal group, mice in the model group had lower values of left ventricular ejection fraction(LVEF) and left ventricular fractional shorte-ning(LVFS), higher values of left ventricular internal diastolic end-diastolic(LVIDd), left ventricular internal diastolic end-systolic(LVIDs), NT-proBNP, TNF-α, and IL-6(P<0.01); the number of macrophages increased in cardiac tissues(P<0.05), and the values of M1-F4/80~+CD86~+ were increased(P<0.01), while the values of M2-F4/80~+CD163~+ decreased(P<0.05); the mRNA and protein expressions of TLR4, myeloid differentiation factor 88(MyD88), IκB kinase α(IKKα), and NF-κB p65 in myocardial tissues were significantly elevated(P<0.05, P<0.01). Compared with the model group, mice in the Shenfu Injection and TAK-242 groups showed elevated LVEF, LVFS, IL-10, and Arg-1 levels, and decreased LVIDd, LVIDs, NT-proBNP, TNF-α, and IL-6 levels(P<0.05, P<0.01); the cardiac F4/80~+CD11b~+(macrophage) and M1-F4/80~+ CD86~+ values were significantly down-regulated, while M2-F4/80~+CD163~+ values were increased(P<0.05, P<0.01); and the mRNA and protein expressions of TLR4, MyD88, IKKα, and NF-κB p65 in myocardial tissues were notably decreased(P<0.05, P<0.01). CHF mice have an imbalance of M1/M2 macrophage polarization, with M1-type macrophages predominating. Shenfu Injection promotes macrophage polarization towards M2, inhibits M1-type macrophage activation, and attenuates inflammatory responses in heart failure by regulating the TLR4/NF-κB signaling pathway.

Cytoprotective and Anti-inflammatory Effects of Derma Genie™-H002 against Paraphenylenediamine-induced Cytotoxicity and Inflammation in RAW 264.7 Cells

Purpose: This study aimed to establish an <i>in vitro</i> model to examine paraphenylenediamine (PPD)-induced cytotoxicity and inflammation within RAW 264.7 cells. Additionally, we investigated the cytoprotective and anti-inflammatory effects of Derma Genie™-H002 derived from extracts of five medicinal herbs. Methods: Various biochemical analyses, including water-soluble tetrazolium salt, crystal violet staining, and lactate dehydrogenase leakage assays, were employed to evaluate the impact of Derma Genie™-H002 on PPD-induced cytotoxicity and inflammation. Furthermore, apoptosis- and inflammation-related gene expression was analyzed using reverse transcription-polymerase chain reaction and Western blotting. Results: Derma Genie™-H002 exhibited no significant cytotoxicity in RAW 264.7 cells, whereas PPD induced notable cytotoxicity at concentrations >25 μM. Cotreatment with PPD and Derma Genie™-H002 not only improved cell proliferation rates but also alleviated cell viability in PPD-induced RAW 264.7 cells. Furthermore, findings demonstrated that Derma Genie™-H002 mitigates the cytotoxicity of PPD-induced RAW 264.7 cells by reducing the expression of the proapoptotic protein Bax and increasing the expression of the antiapoptotic protein Bcl-2. Moreover, cotreatment with PPD and Derma Genie™-H002 downregulated the mRNA expression of inflammasome-related genes, inflammatory cytokines, and allergic contact dermatitis-related genes, all elevated by PPD. The increased expression of nuclear factor-κB protein induced by PPD was also reduced upon cotreatment with Derma Genie™-H002, providing compelling evidence of its anti-inflammatory efficacy in the PPD-induced inflammation model. Conclusion: This study demonstrated that Derma Genie™-H002 effectively alleviates PPD-induced cytotoxicity and inflammation in RAW 264.7 cells. Therefore, the potential application of Derma Genie™-H002 as a naturally derived functional anti-inflammatory material has been validated.

Roxadustat Attenuates Adverse Remodeling Following Myocardial Infarction in Mice.

We evaluated roxadustat's impact on HIF-1 stimulation, cardiac remodeling, and function after MI. Therefore, we analyzed nuclear HIF-1 expression, the mRNA and protein expression of key HIF-1 target genes (RT-PCR, Western blot), inflammatory cell infiltration (immunohistochemistry), and apoptosis (TUNEL staining) 7 days after MI. Additionally, we performed echocardiography in male and female C57BL/6 mice 28 days post-MI. We found a substantial increase in nuclear HIF-1, associated with an upregulation of HIF-1α target genes like CXCL12/CXCR4/ACKR3 at the mRNA and protein levels. Roxadustat increased the proportion of myocardial reparative M2 CD206+ cells, suggesting beneficial alterations in immune cell migration and a trend towards reduced apoptosis. Echocardiography showed that roxadustat treatment significantly preserved ejection fraction and attenuated subsequent ventricular dilatation, thereby reducing adverse remodeling. Our findings suggest that roxadustat is a promising clinically approved treatment option to preserve myocardial function by attenuating adverse remodeling.

Aerobic Exercise Ameliorates Cognitive Disorder and Declined Oxidative Stress via Modulating the Nrf2 Signaling Pathway in D-galactose Induced Aging Mouse Model.

The aim of this research was to explore the potential of treadmill exercise in preventing brain aging and neurodegenerative diseases caused by oxidative stress, by studying its effects on D-galactose-induced mice and the mechanisms involved. The results showed that C57BL/6 mice induced with D-gal exhibited cognitive impairment and oxidative stress damage, which was ameliorated by treadmill exercise. The Morris water maze also showed that exercise improved cognitive performance in aging mice and alleviated hippocampal and mitochondrial damage. The study also found that treadmill exercise increased the expression of nuclear factor Nrf2, p-GSK3β, HO-1, NQO1, BDNF, and Bcl-2 proteins while decreasing the expression of Bax. Furthermore, there was a substantial increase in the levels of CAT, GSH-PX and SOD in the serum, along with a decrease in MDA levels. The outcomes propose that aerobic exercise has the potential to hinder oxidative stress and cell death in mitochondria through the modulation of the Nrf2/GSK3β signaling pathway, thus improving cognitive impairment observed in the aging model induced by D-galactose. It appears that treadmill exercise could potentially serve as an effective therapeutic approach to mitigating brain aging and neurodegenerative diseases triggered by oxidative stress.

Activation of the hypoxia-inducible factor pathway by roxadustat improves glucose metabolism in human primary myotubes from men

Aims/hypothesisHypoxia-inducible factor prolyl 4-hydroxylase (HIF-P4H) enzymes regulate adaptive cellular responses to low oxygen concentrations. Inhibition of HIF-P4Hs leads to stabilisation of hypoxia-inducible factors (HIFs) and activation of the HIF pathway affecting multiple biological processes to rescue cells from hypoxia. As evidence from animal models suggests that HIF-P4H inhibitors could be used to treat metabolic disorders associated with insulin resistance, we examined whether roxadustat, an HIF-P4H inhibitor approved for the treatment of renal anaemia, would have an effect on glucose metabolism in primary human myotubes.MethodsPrimary skeletal muscle cell cultures, established from biopsies of vastus lateralis muscle from men with normal glucose tolerance (NGT) (n=5) or type 2 diabetes (n=8), were treated with roxadustat. Induction of HIF target gene expression was detected with quantitative real-time PCR. Glucose uptake and glycogen synthesis were investigated with radioactive tracers. Glycolysis and mitochondrial respiration rates were measured with a Seahorse analyser.ResultsExposure to roxadustat stabilised nuclear HIF1α protein expression in human myotubes. Treatment with roxadustat led to induction of HIF target gene mRNAs for GLUT1 (also known as SLC2A1), HK2, MCT4 (also known as SLC16A4) and HIF-P4H-2 (also known as PHD2 or EGLN1) in myotubes from donors with NGT, with a blunted response in myotubes from donors with type 2 diabetes. mRNAs for LDHA, PDK1 and GBE1 were induced to a similar degree in myotubes from donors with NGT or type 2 diabetes. Exposure of myotubes to roxadustat led to a 1.4-fold increase in glycolytic rate in myotubes from men with NGT (p=0.0370) and a 1.7-fold increase in myotubes from donors with type 2 diabetes (p=0.0044), with no difference between the groups (p=0.1391). Exposure to roxadustat led to a reduction in basal mitochondrial respiration in both groups (p<0.01). Basal glucose uptake rates were similar in myotubes from donors with NGT (20.2 ± 2.7 pmol mg−1 min−1) and type 2 diabetes (25.3 ± 4.4 pmol mg−1 min−1, p=0.4205). Treatment with roxadustat enhanced insulin-stimulated glucose uptake in myotubes from donors with NGT (1.4-fold vs insulin-only condition, p=0.0023). The basal rate of glucose incorporation into glycogen was lower in myotubes from donors with NGT (233 ± 12.4 nmol g−1 h−1) than in myotubes from donors with type 2 diabetes (360 ± 40.3 nmol g−1 h−1, p=0.0344). Insulin increased glycogen synthesis by 1.9-fold (p=0.0025) in myotubes from donors with NGT, whereas roxadustat did not affect their basal or insulin-stimulated glycogen synthesis. Insulin increased glycogen synthesis by 1.7-fold (p=0.0031) in myotubes from donors with type 2 diabetes. While basal glycogen synthesis was unaffected by roxadustat, pretreatment with roxadustat enhanced insulin-stimulated glycogen synthesis in myotubes from donors with type 2 diabetes (p=0.0345).Conclusions/interpretationRoxadustat increases glycolysis and inhibits mitochondrial respiration in primary human myotubes regardless of diabetes status. Roxadustat may also improve insulin action on glycogen synthesis in myotubes from donors with type 2 diabetes.Graphical

Meta-analysis towards FSHD reveals misregulation of neuromuscular junction, nuclear envelope, and spliceosome

Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common autosomal dominant muscle disorders, yet no cure or amelioration exists. The clinical presentation is diverse, making it difficult to identify the actual driving pathomechanism among many downstream events. To unravel this complexity, we performed a meta-analysis of 13 original omics datasets (in total 171 FSHD and 129 control samples). Our approach confirmed previous findings about the disease pathology and specified them further. We confirmed increased expression of former proposed DUX4 biomarkers, and furthermore impairment of the respiratory chain. Notably, the meta-analysis provides insights about so far not reported pathways, including misregulation of neuromuscular junction protein encoding genes, downregulation of the spliceosome, and extensive alterations of nuclear envelope protein expression. Finally, we developed a publicly available shiny app to provide a platform for researchers who want to search our analysis for genes of interest in the future.