Journal of Molecular Histology最新文献

High doses of ionizing radiation have biohazard effects on living tissues, causing severe inflammation followed by some burns and may cause damage. In the current model for radiation damage effect on the dental pulp of rats. Herein, an extract of the leaves of Carica papaya was examined for its potential protective effect on dental pulp damage caused by Gamma irradiation. Thirty adult male rats were utilised in this study and allocated into five groups (n = 6). The extract’s total antioxidant activity, oxygen radical antioxidant capacity, and iron II chelating activity were quantified. Phytochemical analysis of the extract was conducted utilising LC–ESI–MS/MS, chromatographic separation, and NMR spectroscopy. The extract’s antioxidant and anti-inflammatory properties against radiation-induced damage were assessed. Phytochemical analysis identified 12 phenolic compounds and 3 fatty acids. The levels of CAT and SOD were enhanced during pre-irradiation therapy; MDA lipid peroxidation was diminished; and the levels of COX2, PGE2, and LTB4 were markedly reduced. Histopathological examination of the irradiated group revealed apoptotic odontoblasts bordering an uneven predentin layer, areas of dentin resorption showing multinucleated giant cells, and distinctly detected osteo-dentin formation within the dental pulp. In specimens from the protected group, odontoblasts delineated a consistently thickened predentin layer, fibroblasts displayed normal morphology, and veins and lymphatics were extensively dilated, accompanied by peripheral thrombi and an absence of red blood cells in the lymphatic system. Further, the expression of cleaved caspase-3 was significantly elevated in the irradiated group and markedly reduced in the protected group, as demonstrated by immunohistochemical analysis, indicating that papaya can mitigate substantial dental pulp tissue damage caused by irradiation when employed as a prophylactic agent.

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Background

Cardiac lipid metabolism is easily affected by the surrounding environment, which is involved in the development of heart disease. Salvianolic acid A (SAA) is a phenolic acid with good therapeutic effects on cardiovascular disease. However, the mechanism of how SAA coordinates the crosstalk of oxidative stress and inflammation to reduce the lipid induced-cardiomyocyte injury has not been reported. This study aimed to explore how SAA alleviates lipotoxicity of cardiomyocytes by regulating the crosstalk of oxidative stress and inflammation.

Methods

Palmitate (PA)-injured H9c2 model was used to mimic lipotoxic myocardial injury. Cardiomyocyte viability and damage was detected by CCK-8 and LDH assay, respectively. Apoptosis was evaluated by TUNEL staining. Intracellular lipid accumulation was detected by fluorescent lipid probe. Inflammation cytokines (IL-1β, TNF-α and IL-6) and oxidative stress levels (ROS, SOD and MDA) were examined as well. Meanwhile, levels of related proteins involved in Akt/Nrf2/NF-κB axis were determined by western blotting and immunofluorescent staining. Furthermore, Akt inhibitor (MK2206) and si-Nrf2 RNA were used to preliminarily confirm the mechanism of SAA on regulating oxidative stress and inflammation crosstalk.

Results

SAA memorably alleviated PA-injured H9c2 cardiomyocytes from apoptosis, oxidative stress and inflammation. SAA increased the levels of Akt and GSK-3β phosphorylation and nuclear translocation of Nrf2, while decreased the levels of NF-κB phosphorylation and nuclear translocation. Furthermore, the anti-apoptosis and anti-oxidation effects of SAA were restrained as a result of the MK2206 intervention, while the anti-inflammatory effects partially disappeared due to the silenced Nrf2.

Conclusion

SAA prevents PA-induced cardiotoxicity by orchestrating oxidative stress and inflammation via Akt/Nrf2/NF-κB axis.

Silica nanoparticles (SiO₂-NPs) are very desirable candidates for gene and drugs carriers due to their adjustable biocompatibility, but can negatively affect the vital organs like brain. Liposomal Curcumin (LP-Cur) is recognized for its significant anti-inflammatory, anti-apoptotic, and antioxidant properties. Therefore, this study aimed to investigate the potential protective role of LP-Cur against neurotoxicity induced by SiO₂-NPs (spherical with average particle size 108.80 ± 9.6 nm) in albino rat brain models. Forty adult male albino rats (average weight (170 ± 20 g)) were categorized into four distinct groups: Group I (control group) received 0.9% saline intraperitoneally, Group II (SiO₂-NPs exposed group) was intraperitoneally injected with SiO₂-NPs at the concentration of 200 mg/kg body weight daily, Group III (SiO₂-NPs + LP-Cur group) was treated with SiO₂-NPs (200 mg/kg/day) followed by LP-Cur (80 mg/kg/day) orally, and Group IV (LP-Cur group) was orally administered with 80 mg/kg/day. All therapies were administered over a thirty-day period. Subsequently, the rodents underwent a behavioral, biochemical, histological, and immunohistochemical assessment. This study demonstrated that exposure to SiO₂-NPs adversely affect memory and cognitive function. They significantly increased malondialdehyde (MDA) and decreased the reduced glutathione levels. Furthermore, SiO2-NPs significantly decreased the expression of AChE, Nrf-2, and SOD genes, while increasing the expression of caspase-3 and caspase-9 genes. Moreover, SiO₂-NPs produced serious histological alterations including increased pericellular spaces vacuolation of the neuropil, vascular dilatation, neuronal degeneration and pyknosis. In addition to an intense caspase-3 and GFAP immunoreaction. However, administering LP-Cur alleviated the neurotoxic effects induced by SiO₂-NPs through its potent antioxidant, anti-inflammatory, and anti-apoptotic properties as the liposomal curcumin helps reduce oxidative stress, inhibit lipid peroxidation, and modulate inflammatory signaling pathways such as NF-κB and Nrf2. These effects collectively contribute to protecting cells and tissues from damage induced by SiO₂-NPs. Consequently, liposomal curcumin represents a promising therapeutic strategy for preventing or mitigating the progression of oxidative stress–related diseases.

Maternal diabetes mellitus (MDM) is associated with an increased risk of fetal and placental malformations compared with normal pregnancies. The leaf extract of Azadirachta indica (neem) has been employed as a bioactive agent with proven antidiabetic potential. Beyond its hypoglycemic effects, neem extract has been reported to reduce inflammatory markers, ameliorate insulin resistance, and enhance blood circulation. In the present study, pregnant female rats were allocated into four experimental groups: (I) control (C), (II) neem-treated (N), (III) type 2 diabetes mellitus–induced (D), and (IV) diabetic pregnant rats treated with neem extract (D + N). Diabetic dams exhibited marked elevations in serum glucose, insulin, and lipid profile parameters. Moreover, a significant increase in IFN-γ and IFN-γ/IL-10 ratio, accompanied by a significant reduction in IL-10 levels, was recorded in comparison with controls. Treatment of diabetic dams with neem extract resulted in significant improvements in maternal body weight, reproductive performance, and fetal morphology relative to untreated diabetic rats. Histopathological examination of placental tissues revealed that neem supplementation normalized the decidual layer, increased its thickness, and enhanced the structure of the junctional zone (JZ) and labyrinth zone (LZ) compared to diabetic controls. In conclusion, administration of Azadirachta indica leaf extract demonstrated protective effects against diabetes-induced alterations in pregnancy. It improved maternal metabolic and inflammatory profiles, enhanced reproductive outcomes, and preserved the histological integrity of placental tissues in diabetic rats.

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Chlorpyrifos, an organophosphorus pesticide commonly used in agriculture, has been associated with nephrotoxicity and other harmful effects. This study investigates the renoprotective effects of diosmin, a flavonoid known for its antioxidant and anti-inflammatory properties, against chlorpyrifos-induced kidney damage in rats. Male Wistar albino rats were exposed to chlorpyrifos at a dose of 10 mg/kg for 28 days, and the protective role of diosmin at a dose of 50 mg/kg, orally, was assessed through various biochemical, histopathological, molecular, and computational analyses. Chlorpyrifos exposure significantly induced kidney damage by elevation of kidney functions and NGAL, as well as histopathological alteration. In addition, chlorpyrifos exposure induced renal inflammation as evidenced by upregulation of TLR4, HMGB1, p-NF-κB, TNF-α, IL-1β, and MPO levels. Besides, chlorpyrifos induced oxidative stress as evidenced by decreasing PPAR-γ, SIRT1, GSH, and SOD expressions associated with increased MDA levels. Furthermore, chlorpyrifos induced renal cell apoptosis, as proved by Bax and Bcl2 dysregulation. Interestingly, co-administration of diosmin with chlorpyrifos ameliorated these effects, restoring kidney function biomarkers, preserving histological structure, suppressing inflammatory burden, reducing oxidative stress parameters, and inhibiting apoptosis. In addition, the results of molecular docking confirmed the in vivo results. Taken together, diosmin exerts a renoprotective effect by attenuating chlorpyrifos-induced oxidative stress and inflammation, highlighting its potential as a therapeutic agent for mitigating pesticide-induced kidney injury.

Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance and hyperglycemia. Adverse effects of synthetic antidiabetic drugs encourage interest in Ayurvedic alternatives. This study evaluated Diabepat Kadha, an Ayurvedic polyherbal formulation (HF), in streptozotocin (STZ) and nicotinamide (NA)-induced diabetic Sprague Dawley rats. T2DM was induced by 10% fructose solution for 14 days, followed by STZ (75 mg/kg) + NA (110 mg/kg) (STZ-NA) injection. Animals received 28-day treatments. Assessments included weekly glucose monitoring, oral glucose tolerance test (OGTT), serum insulin, creatinine, bleeding, clotting times, liver histopathology, skeletal muscle Glucose Transporter Type 4 (GLUT4 ) estimation, and gastric necropsy. STZ-NA significantly increased blood glucose (> 250 mg/dl) by day 4. HF (3 mL/kg), Metformin 200 mg/kg (M 200), and combination of HF(3 ml/kg) + Metformin 100 mg/kg (HF + M100) significantly reduced fasting glucose, restored insulin levels with favorable changes in HOMA indices, indicating enhanced insulin sensitivity and significant upregulation of. GLUT4 expression. OGTT exhibited improved glucose clearance, especially with HF + M100, restoring normalized levels within 120 min. Serum creatinine, bleeding, and clotting times remained unaltered. Diabetic controls showed marked hepato-cellular damage while treated groups exhibited near-normal hepatic architecture without gastric pathology. Diabepat Kadha demonstrated significant antidiabetic efficacy comparable to Metformin, with enhanced efficacy in combination. The formulation improved insulin sensitivity and glycemic control, primarily through upregulation of skeletal muscle GLUT4 expression by enhancement of insulin signaling and protection of hepatic architecture against STZ-induced injury as a result of synergy among various phytoconstituents in the formulation. Favorable safety profile further supports its therapeutic potential in T2DM management.

Myocardial ischemia/reperfusion (I/R) injury represents a major clinical challenge, and ferroptosis has been identified as a crucial mechanism of cardiomyocyte death. While RNA N6-methyladenosine (m6A) modification is a dynamic regulator of gene expression, its role in myocardial I/R injury remains poorly defined. This study investigates the function of the m6A demethylase ALKBH5 and its underlying mechanism in counteracting ferroptosis during I/R injury. Using both ex vivo Langendorf I/R model, in vivo mouse I/R model and in vitro cardiomyocyte hypoxia/reoxygenation (H/R) models, we found that ALKBH5 expression was significantly downregulated, leading to global RNA m6A hypermethylation. ALKBH5 overexpression conferred robust cardioprotection, improving cardiac function, and reducing infarct size in mice, while enhancing cell viability and preserving mitochondrial membrane potential in cardiomyocytes. Mechanistically, RNA sequencing and mechanistic studies revealed that ALKBH5 directly binds to and demethylates m6A modifications on the mRNA of ferroptosis suppressor protein 1 (FSP1), thereby enhancing its mRNA stability and protein expression. The upregulation of FSP1 inhibited ferroptosis, as evidenced by reduced lipid peroxidation, iron overload, and reactive oxygen species accumulation, alongside increased levels of glutathione peroxidase 4 (GPX4). Crucially, the protective effects of ALKBH5 were mimicked by the ferroptosis inhibitor ferrostatin-1 and were completely abolished by FSP1 knockdown. Our findings unveil a novel ALKBH5/m6A/FSP1 signaling axis that critically suppresses ferroptosis, highlighting the therapeutic potential of targeting epitranscriptomic mechanisms for the treatment of ischemic heart disease.

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ALKBH5 expression is dynamically reduced in response to myocardial I/R insult. ALKBH5-mediated demethylation of specific RNA transcripts, orchestrated by its catalytic activity, mitigates ferroptosis by regulating the expression of key ferroptosis-related genes. Importantly, we identify ferroptosis-suppressor-protein 1 (FSP1) as a downstream effector of ALKBH5-mediated m6A demethylation, linking the protective effects of ALKBH5 to the inhibition of ferroptosis in cardiomyocytes.

Severe burn injuries cause increased endothelial permeability leading to systemic capillary leak and massive fluid shifts into the extravascular space. Excessive fluid resuscitation to ensure sufficient end-organ perfusion results in critical tissue oedema. The present study assessed the underlying microscopic data regarding the integrity of thin skin dermal capillary endothelial barrier and angiogenesis after high-dose vitamin C (HDVC) administration in severely burned patients at days 1, 3 and 7 postburn. Twenty severely burned patients [20% to 25% total body surface area of second deep dermal type] were enrolled in this study. Ten patients received high-dose vitamin C infusion in a dose of 10g within the first 24 h of admission (HDVC burned group) and 10 patients did not (burned group). Patients were selected from the Burn Intensive Care Unit at El-Demerdash Hospital, Ain Shams University. On the microscopic level, HDVC infusion significantly reduced inflammation as evidenced by decreased iNOS immuno-expression and inflammatory cell count, markedly improved tissue barrier function as expressed in enhanced occludin immune-reactivity, significantly decreased the mean area percentage of dermal capillaries, and promoted angiogenesis through increased immuno-expression over time in skin punch biopsies. Overall, HDVC seems promising as an adjunct therapy in burn management, but further investigation is required on clinical grounds to determine the appropriate dose for HDVC infusion and explore its long-term outcome.

Premature Ovarian Insufficiency (POI) is a critical condition characterized by accelerated depletion of the ovarian follicle reserve. 7,12-dimethylbenz[a]anthracene (DMBA) is a potent carcinogen that induces ovarian toxicity and follicle depletion, making it a widely used model for POI and menopausal research. This study investigates the molecular effects of DMBA on the ovarian reserve, specifically focusing on the expression and activity of c-Abl tyrosine kinase and mouse telomerase reverse transcriptase (mTERT). Our findings confirm that DMBA exposure leads to a significant decrease in follicle numbers and an increase in atretic follicles, consistent with ovotoxicity. Molecular analysis revealed a simultaneous decrease in c-Abl tyrosine kinase activity and an increase in mTERT protein expression in the mouse ovary. These molecular changes are associated with altered follicle numbers and follicular development. In addition to confirming previously reported ovotoxic effects, our work provides novel, quantitative evidence of a DMBA-induced discrepancy between c-Abl and mTERT expression at the protein level, suggesting a post-transcriptional regulatory mechanism that contributes to the development of POI.

Idiopathic pulmonary fibrosis (IPF) is identified as a chronic, progressive fibrotic interstitial pneumonia of unknown cause. Echinacoside (ECH) is a phenylethanoid glycoside extracted from Cistanche deserticola, which exhibits noteworthy anti-oxidant and anti-inflammatory activities and can protect against renal, myocardial, and kidney fibrosis. This study aimed to assess the therapeutic effect of ECH on IPF by using cellular and animal experiments. Bleomycin (BLM)-induced IPF mice and transforming growth factor (TGF)-β1-treated human embryonic lung fibroblasts (MRC-5) were respectively used as animal and cellular models of IPF, which were then subjected to ECH treatment. Mouse pulmonary tissues were harvested for hematoxylin and eosin (H&E), Masson’s trichrome, immunohistochemical, and immunofluorescence staining, RT-qPCR, and western blotting to determine pulmonary histological changes and the expression of fibrosis-related genes (α-SMA, fibronectin, and COL1A1), M2 macrophage markers (CD206, CD163, Arg-1, and YM-1), and phosphorylated JAK2 and STAT3. Bronchoalveolar lavage fluid (BALF) was collected to detect total protein contents, total inflammatory cell counts, pro-inflammatory cytokine (TNF-α and IL-1β) levels, and pro-fibrosis factor TGF-β content. Cell viability and migration and ⍺-SMA, fibronectin, COL1A1, and phosphorylated JAK2 and STAT3 levels in MRC-5 cells were assessed through CCK-8 assay, wound healing assay, RT-qPCR, and western blotting. ECH administration significantly mitigated BLM-induced pulmonary inflammation and fibrosis in mice. ECH decreased total protein contents, total leukocyte counts, TNF-α and IL-1β levels, and TGF-β contents in BALF as well as hydroxyproline contents and α-SMA, fibronectin, COL1A1, CD206, CD163, Arg-1, and YM-1 levels in pulmonary tissues of BLM-induced IPF mice. In vitro data revealed that ECH markedly inhibited the upregulation of ⍺-SMA, fibronectin, and COL1A1 expression and cell migration induced by TGF-β1 in MRC-5 cells. From a mechanistic standpoint, ECH treatment inhibited phosphorylated JAK2 and STAT3 levels both in vivo and in vitro. ECH exhibits an anti-fibrotic effect in IPF by inhibiting pro-fibrotic M2 macrophage polarization, which might be attributed to its downregulation of the JAK2/STAT3 pathway. This discovery emphasizes the potential of ECH as a promising therapeutic agent for IPF treatment.