Mitochondrial metabolism is crucial for providing energy and heme precursors during erythroid development. Oxoglutarate dehydrogenase complex (OGDC) is a key enzyme in the mitochondrial tricarboxylic acid (TCA) cycle, and its level gradually increases during erythroid development, indicating its significant role in erythroid development. The aim of the present study was to explore the role and mechanism of OGDC in erythroid development. In this study, we treated erythroid progenitor cells with CPI-613, a novel lipoic acid analog that competitively inhibits OGDC. The results showed that CPI-613 inhibited erythropoietin (EPO)-induced differentiation and enucleation of human CD34⁺ hematopoietic stem cells into erythroid cells, suppressed cell proliferation, and induced apoptosis. The results of in vivo experiments showed that CPI-613 also hindered the recovery of mice from acute hemolytic anemia. Further mechanism research results showed that CPI-613 increased reactive oxygen species (ROS) in erythroid progenitor cells, inhibited mitochondrial respiration, caused mitochondrial damage, and suppressed heme synthesis, thereby inhibiting erythroid differentiation. Clinical research results showed that oxoglutarate dehydrogenase (OGDH) protein expression levels were up-regulated in bone marrow cells of polycythemia vera (PV) patients. Treatment with CPI-613 significantly inhibited the excessive proliferation and differentiation of erythroid progenitor cells of the PV patients. These findings demonstrates the critical role of OGDC in normal erythroid development, suggesting that inhibiting its activity could be a novel therapeutic strategy for treating PV.
Animals ; Humans ; Mitochondria/metabolism* ; Mice ; Ketoglutarate Dehydrogenase Complex/physiology* ; Cell Differentiation/drug effects* ; Cells, Cultured ; Erythropoiesis/drug effects* ; Reactive Oxygen Species/metabolism* ; Cell Proliferation/drug effects* ; Erythroid Precursor Cells/cytology* ; Apoptosis/drug effects* ; Thioctic Acid/pharmacology* ; Caprylates ; Sulfides

This study investigated the mechanism of autophagy in the differentiation processes of MC3T3-E1 cells under osteogenic induction(physiological) and alcohol(AL) intervention(pathological), as well as the mechanism by which icariin(ICA) affected osteogenic differentiation of MC3T3-E1 cells under the pathological condition of AL intervention. Osteogenic mineralized nodule staining confirmed that the cells could differentiate into osteoblasts. After determining the appropriate concentrations of AL and ICA using the CCK-8 assay, seven groups were set up in this study: complete medium(CM) group, osteogenic induction medium(OIM) group, OIM+0.25 mol·L~(-1) AL group, OIM+0.25 mol·L~(-1) AL+1×10~(-8) mol·L~(-1) ICA group, OIM+0.25 mol·L~(-1) AL+1×10~(-7) mol·L~(-1) ICA group, OIM+0.25 mol·L~(-1) AL+1×10~(-6) mol·L~(-1) ICA group, and OIM+0.25 mol·L~(-1) AL+1×10~(-5) mol·L~(-1) ICA group, with a culture period of 7 days. Alkaline phosphatase(ALP) staining was used to detect the relative ALP area. Western blot and RT-qPCR were employed to analyze the expression of osteogenesis-and autophagy-related proteins and mRNAs. Reactive oxygen species(ROS) staining was used to detect ROS levels, and apoptosis was assessed through mitochondrial membrane potential assays. The results showed that ICA increased the relative ALP area that had been reduced by AL intervention. AL down-regulated the expression levels of Wnt family member 1(Wnt1), along with the osteogenesis-related mRNAs Wnt1, β-catenin, Runt-related transcription factor 2(Runx2), osteoprotegerin(OPG), and ALP, thereby inhibiting osteogenic differentiation. ICA up-regulated the expression levels of the osteogenesis-related proteins and mRNAs that had been inhibited by AL, promoting osteogenic differentiation. AL inhibited typical autophagy, while ICA regulated Rubicon to suppress LC3-associated phagocytosis(LAP) and promote typical autophagy. ICA also reduced the ROS levels that were elevated by AL and decreased the apoptosis of osteoblasts induced by AL intervention. In conclusion, ICA can regulate Rubicon to inhibit LAP, promote typical autophagy, eliminate ROS, reduce apoptosis, and ultimately enhance the osteogenic differentiation of MC3T3-E1 cells under the pathological condition of AL intervention by modulating the Wnt/β-catenin signaling pathway.
Autophagy/drug effects* ; Animals ; Osteogenesis/drug effects* ; Mice ; Cell Differentiation/drug effects* ; Osteoblasts/metabolism* ; Ethanol/pharmacology* ; Flavonoids/pharmacology* ; Cell Line ; Reactive Oxygen Species/metabolism* ; Drugs, Chinese Herbal/pharmacology*

Guided by the theory of "the kidney storing essence, governing the bones, and producing marrow", this study explored the mechanism of icariin(ICA) in regulating the osteogenic differentiation of rat bone mesenchymal stem cells(BMSCs) through caveolin-1(Cav1) via in vitro and in vivo experiments, aiming to provide a theoretical basis for the prevention and treatment of postmenopausal osteoporosis with traditional Chinese medicine(TCM). Primary cells were obtained from 4-week-old female SD rats using the whole bone marrow adherent method. Flow cytometry was used to detect the expression of surface markers CD29, CD90, CD11b, and CD45. The potential for osteogenic and adipogenic differentiation was assessed. The effect of ICA on cell viability was determined using the CCK-8 assay, and the impact of ICA on the formation of mineralized nodules was verified by alizarin red staining. A stable Cav1-silenced cell line was constructed using lentivirus. The effect of Cav1 silencing on osteogenic differentiation was observed via alizarin red staining. Western blot analysis was conducted to detect the expression of Cav1, Hippo/TAZ, and osteogenic markers such as Runt-related transcription factor 2(RUNX2) and alkaline phosphatase(ALP). The results showed that primary cells were successfully obtained using the whole bone marrow adherent method, positively expressing surface markers of rat BMSCs and possessing the potential for both osteogenic and adipogenic differentiation. The CCK-8 assay and alizarin red staining results indicated that 1×10~(-7) mol·L~(-1) was the optimal concentration of ICA for intervention in this experiment(P<0.05). During osteogenic induction, ICA inhibited Cav1 expression(P<0.05) while promoting TAZ expression(P<0.05). Alizarin red staining demonstrated that Cav1 silencing significantly promoted the osteogenic differentiation of BMSCs. After ICA intervention, TAZ expression was activated, and the expression of osteogenic markers ALP and RUNX2 was increased. In conclusion, Cav1 silencing significantly promotes the osteogenic differentiation of BMSCs, and ICA promotes this differentiation by inhibiting Cav1 and regulating the Hippo/TAZ signaling pathway.
Animals ; Mesenchymal Stem Cells/metabolism* ; Caveolin 1/genetics* ; Osteogenesis/drug effects* ; Rats, Sprague-Dawley ; Rats ; Cell Differentiation/drug effects* ; Female ; Signal Transduction/drug effects* ; Flavonoids/administration & dosage* ; Protein Serine-Threonine Kinases/genetics* ; Drugs, Chinese Herbal/pharmacology* ; Cells, Cultured ; Humans

OBJECTIVE: To investigate the antioxidant and osteogenic induction capabilities of calcium phosphate nanoflowers (hereinafter referred to as nanoflowers) in vitro at different concentrations. METHODS: Nanoflowers were prepared using gelatin, tripolyphosphate, and calcium chloride. Their morphology, microstructure, elemental composition and distribution, diameter, and molecular constitution were characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy-dispersive spectroscopy. Femurs and tibias were harvested from twelve 4-week-old Sprague Dawley rats, and bone marrow mesenchymal stem cells (BMSCs) were isolated and cultured using the whole bone marrow adherent method, followed by passaging. The third passage cells were identified as stem cells by flow cytometry and then co-cultured with nanoflowers at concentrations of 0, 0.4, 0.8, 1.2, 1.6, 2.0, 2.4, 2.8, 3.2, and 3.6 mg/mL. Cell counting kit 8 (CCK-8) assay was performed to screen for the optimal concentration that demonstrated the best cell viability, which was subsequently used as the experimental concentration for further studies. After co-culturing BMSCs with the screened concentration of nanoflowers, the biocompatibility of the nanoflowers was verified through live/dead cell staining, scratch assay, and cytoskeleton staining. The antioxidant capacity was assessed by using reactive oxygen species (ROS) fluorescence staining. The in vitro osteoinductive ability was evaluated via alkaline phosphatase (ALP) staining, alizarin red staining, and immunofluorescence staining of osteocalcin (OCN) and Runt-related transcription factor 2 (RUNX2). All the above indicators were compared with the control group of normally cultured BMSCs without the addition of nanoflowers. RESULTS: Scanning electron microscopy revealed that the prepared nanoflowers exhibited a flower-like structure; transmission electron microscopy scans discovered that the nanoflowers possessed a multi-layered structure, and high-magnification images displayed continuous atomic arrangements, with the nanoflower diameter measuring (2.00±0.25) μm; energy-dispersive spectroscopy indicated that the nanoflowers contained elements such as C, N, O, P, and Ca, which were uniformly distributed across the flower region; Fourier transform infrared spectroscopy analyzed the absorption peaks of each component, demonstrating the successful preparation of the nanoflowers. Through CCK-8 screening, the concentrations of 0.8, 1.2, and 1.6 mg/mL were selected for subsequent experiments. The live/dead cell staining showed that nanoflowers at different concentrations exhibited good cell compatibility, with the 1.2 mg/mL concentration being the best (P<0.05). The scratch assay results indicated that the cell migration ability in the 1.2 mg/mL group was superior to the other groups (P<0.05). The cytoskeleton staining revealed that the cell morphology was well-extended in all concentration groups, with no significant difference compared to the control group. The ROS fluorescence staining demonstrated that the ROS fluorescence in all concentration groups decreased compared to the control group after lipopolysaccharide induction (P<0.05), with the 1.2 mg/mL group showing the weakest fluorescence. The ALP staining showed blue-purple nodular deposits around the cells in all groups, with the 1.2 mg/mL group being significantly more prominent. The alizarin red staining displayed orange-red mineralized nodules around the cells in all groups, with the 1.2 mg/mL group having more and denser nodules. The immunofluorescence staining revealed that the expressions of RUNX2 and OCN proteins in all concentration groups increased compared to the control group, with the 1.2 mg/mL group showing the strongest protein expression (P<0.05). CONCLUSION The study successfully prepares nanoflowers, among which the 1.2 mg/mL nanoflowers exhibits excellent cell compatibility, antioxidant properties, and osteogenic induction capability, demonstrating their potential as an artificial bone substitute material.
Animals ; Osteogenesis/drug effects* ; Mesenchymal Stem Cells/drug effects* ; Calcium Phosphates/pharmacology* ; Rats, Sprague-Dawley ; Rats ; Antioxidants/chemistry* ; Cells, Cultured ; Cell Differentiation/drug effects* ; Nanostructures/chemistry* ; Tissue Engineering/methods* ; Bone Marrow Cells/cytology* ; Coculture Techniques ; Tissue Scaffolds/chemistry* ; Male ; Biocompatible Materials/chemistry* ; Cell Survival ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Cell Proliferation

OBJECTIVE: To explore the mechanism by which ω-3 polyunsaturated fatty acids (hereinafter referred to as "ω-3") exert antioxidant stress protection and promote osteogenic differentiation in MC3T3-E1 cells, and to reveal the relationship between ω-3 and the key antioxidant stress pathway involving nuclear factor E2-related factor 2 (Nrf2) and NAD (P) H quinone oxidoreductase 1 (NQO1) in MC3T3-E1 cells. METHODS: The optimal concentration of H ₂O ₂ (used to establish the oxidative stress model of MC3T3-E1 cells in vitro) and the optimal intervention concentrations of ω-3 were screened by cell counting kit 8. MC3T3-E1 cells were divided into blank control group, oxidative stress group (H ₂O ₂), low-dose ω-3 group (H ₂O ₂+low-dose ω-3), and high-dose ω-3 group (H ₂O ₂+high-dose ω-3). After osteoblastic differentiation for 7 or 14 days, the intracellular reactive oxygen species (ROS) level was measured by fluorescence staining and flow cytometry, and the mitochondrial morphological changes were observed by biological transmission electron microscope; the expression levels of Nrf2, NQO1, heme oxygenase 1 (HO-1), Mitofusin 1 (Mfn1), and Mfn2 were detected by Western blot to evaluate the cells' antioxidant stress capacity; the expression levels of Runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN) were detected by immunofluorescence staining and Western blot; osteogenic potential of MC3T3-E1 cells was evaluated by alkaline phosphatase (ALP) staining and alizarin red staining. RESULTS: Compared with the oxidative stress group, the content of ROS in the low and high dose ω-3 groups significantly decreased, and the protein expressions of Nrf2, NQO1, and HO-1 significantly increased ( P<0.05). At the same time, the mitochondrial morphology of MC3T3-E1 cells improved, and the expressions of mitochondrial morphology-related proteins Mfn1 and Mfn2 significantly increased ( P<0.05). ALP staining and alizarin red staining showed that the low-dose and high-dose ω-3 groups showed stronger osteogenic ability, and the expressions of osteogenesis-related proteins RUNX2 and OCN significantly increased ( P<0.05). And the above results showed a dose-dependence in the two ω-3 treatment groups ( P<0.05). CONCLUSION ω-3 can enhance the antioxidant capacity of MC3T3-E1 cells under oxidative stress conditions and upregulate their osteogenic activity, possibly through the Nrf2/NQO1 signaling pathway.
Oxidative Stress/drug effects* ; NF-E2-Related Factor 2/metabolism* ; NAD(P)H Dehydrogenase (Quinone)/metabolism* ; Animals ; Mice ; Osteogenesis/drug effects* ; Cell Differentiation/drug effects* ; Fatty Acids, Omega-3/pharmacology* ; Signal Transduction/drug effects* ; Osteoblasts/drug effects* ; Reactive Oxygen Species/metabolism* ; Cell Line ; Hydrogen Peroxide/pharmacology* ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Antioxidants/pharmacology* ; Heme Oxygenase-1/metabolism*

The healing of the tendon-bone interface is a complex dynamic process involving the interaction of multiple cellular and molecular signaling pathways. Bone mesenchymal stem cells (BMSCs) have the potential to differentiate into various types of cells, including osteoblasts, chondrocytes and adipocytes, etc., and have the potential to regenerate damaged tissues. They are potential seed cells for promoting tendon-bone healing. How to precisely regulate the proliferation and differentiation of BMSCs to accelerate the process of tendon-bone healing is a current research hotspot. Monomers of traditional Chinese medicine can promote tendon-bone healing by regulating signaling pathways such as Wnt/β-catenin and BMP/Smad to induce osteogenic and chondrogenic differentiation of BMSCs. This article reviews from several aspects such as the regulatory role of related signaling pathways on tendine-bone healing, traditional Chinese medicine monomers and their mechanism of regulating BMSCs to promote tendine-bone healing in order to providing new ideas for promoting tendine-bone healing.
Mesenchymal Stem Cells/cytology* ; Humans ; Animals ; Bone Marrow Cells/cytology* ; Bone and Bones/drug effects* ; Wound Healing/drug effects* ; Medicine, Chinese Traditional ; Tendons/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Signal Transduction/drug effects* ; Cell Differentiation/drug effects*

Objective To investigate the effect of gentiopicroside on osteogenic differentiation of human bone marrow mesenchymal stem cells (BMSCs), and to determine whether its mechanism involves the stromal cell-derived factor 1(SDF-1)/C-X-C chemokine receptor 4 (CXCR4) pathway. Methods BMSCs were divided into six groups: normal culture control group, osteogenic induction model group, low-dose gentiopicroside (L-gentiopicroside, 10 μmol/L) group, medium-dose gentiopicroside (M-gentiopicroside, 20 μmol/L) group, high-dose gentiopicroside (H-gentiopicroside, 40 μmol/L) group, and H-gentiopicroside+SDF-1/CXCR4 pathway inhibitor (AMD3100) group (H-gentiopicroside+AMD3100, 40 μmol/L gentiopicroside+10 μg/mL AMD3100). Cell viability, apoptosis, ALP activity, mineralized nodule formation, and protein levels of the SDF-1/CXCR4 pathway were assessed using the CCK-8 assay, flow cytometry, ALP staining, Alizarin Red S staining, and Western blotting, respectively. Results No mineralized nodules were observed in either the control and model group, although the color of the model group deepened. Compared with the control group, the model group showed significantly increased A value, ALP activity, expression levels of Runt related transcription factor 2 (RUNX2), osteopontin (OPN), SDF-1, CXCR4 proteins, along with a lower apoptosis rate. Compared with the model group, the L-gentiopicroside, M-gentiopicroside and H-gentiopicroside groups showed dose-dependently (Ldifferentiation of BMSCs may be achieved by activating the SDF-1/CXCR4 signaling pathway.
Humans ; Receptors, CXCR4/genetics* ; Mesenchymal Stem Cells/metabolism* ; Chemokine CXCL12/genetics* ; Iridoid Glucosides/pharmacology* ; Osteogenesis/drug effects* ; Cell Differentiation/drug effects* ; Signal Transduction/drug effects* ; Cells, Cultured ; Apoptosis/drug effects* ; Bone Marrow Cells/metabolism*

OBJECTIVES: To investigate the effect of pachymic acid on brown/beige adipocyte differentiation and lipid metabolism in preadipocytes. METHODS: 3T3-L1 MBX cells were induced to differentiate into beige adipocytes using a brown cocktail method. The impact of pachymic acid on the viability of 3T3-L1 MBX cells was evaluated using the CCK-8 assay. The formation of lipid droplets following treatment with pachymic acid was observed by oil red O staining. The mRNA expression levels of key browning genes, including uncoupling protein (Ucp) 1, the peroxisome proliferator activated receptor-γ coactivator (Pgc)-1α, and the PR domain-containing protein 16 (Prdm16), as well as the mRNA expression of sterol regulatory element-binding protein (Srebp) 1c, acetyl-coA carboxylase (Acc), fatty acid synthase (Fas), and hormone-sensitive triglyceride lipase (Hsl), adipose triglyceride lipase (Atgl), and carnitine palmitoyltransferase (Cpt) 1 were detected by quantitative reverse transcription polymerase chain reaction. The protein expression of Ucp1, Pgc-1a, and Prdm16 was detected by Western blotting. RESULTS: The 3T3-L1 MBX cells were induced in vitro to form beige adipocytes with high expression of key browning genes(Ucp1, Pgc-1α, and Prdm16), and beige adipose-marker genes (Cd137, Tbx1, and Tmem26). Concentrations range of 0-80 μmol/L pachymic acid were non-cytotoxic to 3T3-L1 MBX cells. Pachymic acid treatment significantly inhibited the differentiation of 3T3-L1 MBX cells, resulting in a notable decrease in lipid accumulation. There was a marked increase in the expression of key browning genes and their proteins products, such as Ucp1, Pgc-1α, and Prdm16, while the expressions of fat synthesis-related genes Srebp1c, Acc and Fas were significantly decreased (all P<0.05). The expressions of lipolysis-related genes (Hsl, Atgl, and Cpt1) were significantly increased (all P<0.05). Treatment with 20 μmol/L pachymic acid showed the most pronounced effect. CONCLUSIONS Pachymic acid can inhibit fat synthesis and promote lipid decomposition by regulating the brown formation and lipid differentiation of preadipocytes.
Animals ; Lipid Metabolism/drug effects* ; Mice ; Cell Differentiation/drug effects* ; Adipocytes, Beige/drug effects* ; 3T3-L1 Cells ; Adipocytes, Brown/drug effects* ; Triterpenes/pharmacology* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; Uncoupling Protein 1 ; Sterol Regulatory Element Binding Protein 1/metabolism*

OBJECTIVE: To investigate the Wnt signaling pathway and miRNAs mechanism of extracts of Plastrum Testudinis (PT) in the treatment of osteoporosis (OP). METHODS: Thirty female Sprague Dawley rats were randomly divided into 5 groups by random number table method, including sham group, ovariectomized group (OVX), ovariectomized groups treated with high-, medium-, and low-dose PT (160, 80, 40 mg/kg per day, respectively), with 6 rats in each group. Except for the sham group, the other rats underwent bilateral ovariectomy to simulate OP and received PT by oral gavage for 10 consecutive weeks. After treatment, bone mineral density was measured by dual-energy X-ray absorptiometry; bone microstructure was analyzed by micro-computed tomography and hematoxylin and eosin staining; and the expressions of osteogenic differentiation-related factors were detected by immunochemistry, Western blot, and quantitative polymerase chain reaction. In addition, Dickkopf-1 (Dkk-1) was used to inhibit the Wnt signaling pathway in bone marrow mesenchymal stem cells (BMSCs) and miRNA overexpression was used to evaluate the effect of miR-214 on the osteogenic differentiation of BMSCs. Subsequently, PT extract was used to rescue the effects of Dkk-1 and miR-214, and its impacts on the osteogenic differentiation-related factors of BMSCs were evaluated. RESULTS: PT-M and PT-L significantly reduced the weight gain in OVX rats (P<0.05). PT also regulated the bone mass and bone microarchitecture of the femur in OVX rats, and increased the expressions of bone formation-related factors including alkaline phosphatase, bone morphogenetic protein type 2, collagen type I alpha 1, and runt-related transcription factor 2 when compared with the OVX group (P<0.05 or P<0.01). Meanwhile, different doses of PT significantly rescued the inhibition of Wnt signaling pathway-related factors in OVX rats, and increased the mRNA or protein expressions of Wnt3a, β-catenin, glycogen synthase kinase-3β, and low-density lipoprotein receptor-related protein 5 (P<0.05 or P<0.01). PT stimulated the osteogenic differentiation of BMSCs inhibited by Dkk-1 and activated the Wnt signaling pathway. In addition, the expression of miR-214 was decreased in OVX rats (P<0.01), and it was negatively correlated with the osteogenic differentiation of BMSCs (P<0.01). MiR-214 mimic inhibited Wnt signaling pathway in BMSCs (P<0.05 or P<0.01). Conversely, PT effectively counteracted the effect of miR-214 mimic, thereby activating the Wnt signaling pathway and stimulating osteogenic differentiation in BMSCs (P<0.05 or P<0.01). CONCLUSION PT stimulates bone formation in OVX rats through β-catenin-mediated Wnt signaling pathway, which may be related to inhibiting miR-214 in BMSCs.
Animals ; MicroRNAs/genetics* ; Female ; Rats, Sprague-Dawley ; Wnt Signaling Pathway/genetics* ; Osteogenesis/genetics* ; Mesenchymal Stem Cells/cytology* ; Cell Differentiation/drug effects* ; Bone Density/drug effects* ; Ovariectomy ; Osteoporosis/drug therapy* ; beta Catenin/metabolism* ; Rats ; Intercellular Signaling Peptides and Proteins/metabolism* ; Drugs, Chinese Herbal/pharmacology*

OBJECTIVES: Acute lung injury (ALI) is an acute respiratory failure syndrome characterized by impaired gas exchange. Due to the lack of effective targeted drugs, it is associated with high mortality and poor prognosis. Tripterygium wilfordii (TW) has demonstrated anti-inflammatory activity in the treatment of various diseases. This study aims to investigate the effects and underlying mechanisms of TW on myeloid-derived suppressor cells (MDSCs) in ALI, providing experimental evidence for TW as a potential adjuvant therapy for ALI. METHODS: Eighteen specific pathogen-free (SPF) C57BL/6 mice were randomly divided into normal control (NC; intranasal saline), lipopolysaccharide (LPS; 5 mg/kg intranasally to induce ALI), and LPS+TW (50 mg/kg TW by gavage on the first day of modeling, followed by 5 mg/kg LPS intranasally to induce ALI) groups (n=6 each). Lung injury and edema were assessed by histopathological scoring and wet-to-dry weight ratio. Cytokine levels [interleukin (IL)-1β, IL-6, IL-18, tumor necrosis factor-α (TNF-α)] in lung tissue lavage fluid were measured by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was used to assess the proportions of MDSCs, polymorphonuclear MDSCs (PMN-MDSCs), and monocytic MDSCs (M-MDSCs) in bone marrow, spleen, peripheral blood, and lung tissue, as well as reactive oxygen species (ROS) levels in lung tissues. Messenger RNA (mRNA) expression levels of inducible nitric oxide synthase (iNOS) and arginase-1 (ARG-1) in lung tissues were determined by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). PMN-MDSCs sorted from the lungs of LPS-treated mice were co-cultured with splenic CD3⁺ T cells and divided into NC, triptolide (TPL)-L, and TPL-H groups, with bovine serum albumin, 25 nmol/L TPL, and 50 nmol/L TPL, respectively. Flow cytometry was used to detect the effect of PMN-MDSCs on T-cell proliferation, and RT-qPCR was used to measure iNOS and ARG-1 mRNA expression. RESULTS: Compared with the NC group, the LPS group showed marked lung pathology with significantly increased histopathological scores and wet-to-dry ratios (both P<0.001). TW treatment significantly alleviated lung injury and reduced both indices compared with the LPS group (both P<0.05). Cytokine levels were significantly decreased in the LPS+TW group compared with the LPS group (all P<0.001). The proportions of MDSCs in CD45⁺ cells from spleen, bone marrow, peripheral blood, and lung, as well as PMN-MDSCs from spleen, peripheral blood, and lung, were significantly reduced in the LPS+TW group compared with the LPS group (all P<0.05), accompanied by reduced ROS levels in lung tissues (P<0.001). iNOS and ARG-1 mRNA expression in lung tissues was significantly lower in the LPS+TW group than in the LPS group (both P<0.001). In vitro, compared with the TPL-L group, the TPL-H group showed significantly increased CD3⁺ T-cell proliferation (P<0.001), and decreased iNOS and ARG-1 mRNA expression (all P<0.05). CONCLUSIONS TW alleviates the progression of LPS-induced ALI in mice, potentially by reducing the proportion of MDSCs in lung tissues and attenuating the immunosuppressive function of PMN-MDSCs.
Animals ; Acute Lung Injury/chemically induced* ; Myeloid-Derived Suppressor Cells/cytology* ; Tripterygium/chemistry* ; Mice, Inbred C57BL ; Mice ; Cell Differentiation/drug effects* ; Male ; Lipopolysaccharides ; Nitric Oxide Synthase Type II/genetics* ; Cytokines/metabolism* ; Reactive Oxygen Species/metabolism* ; Diterpenes/pharmacology* ; Epoxy Compounds ; Phenanthrenes