OBJECTIVE: To analyze the influences of dihydromyricetin on the proliferation and apoptosis of chondrocytes in osteoarthritis induced by hydrogen peroxide (H₂O₂) through reactive oxygen species (ROS)/p38 mitogen activated protein kinase (p38-MAPK) pathway. METHODS: Five C57BL/6J mice were euthanized by cervical dislocation after anesthesia. Chondrocytes were extracted and cultured.After passage, the chondrocytes were divided into control group, H2O2 group (0.8 μmol·L^-1 H₂O₂), dihydromyricetin low concentration group (0.8 μmol·L^-1 H₂O₂+20 μmol·L^-1 dihydromyricetin), dihydromyricetin high concentration group (0.8 μmol·L^-1 H₂O₂+80 μmol·L^-1 dihydromyricetin), and ROS inhibitor N-acetylcysteine (NAC) group (0.8 μmol·L^-1 H₂O₂+5 mmol·L^-1 NAC). The activity of chondrocytes was measured by methyl thiazolyl tetrazolium (MTT) assay. The apoptosis rate of chondrocytes was measured by Hoechst 33342 method. The level of ROS in chondrocytes was measured by 2, 7-dichlorofluorescein diacetate (DCFH-DA) fluorescence probe.The level of Type II collagen α1 (Col2α1) mRNA was measured by qRT-PCR.And the expression of Col2α1, p-p38-MAPK/p38-MAPK, B cell lymphoma gene-2 (Bcl-2) and Bcl-2 associated X protein (Bax) proteins was detected by Western blot. RESULTS: The chondrocytes showed swirling fibrous mass, and the expression of COL2α was positive. Compared with the control group, the chondrocyte viability, apoptosis rate, ROS fluorescence intensity, p-p38-MAPK/p38-MAPK, and the expression of Bax protein in H2O22 group increased, the level of Col2α1 mRNA, and the expression of Col2α1 and Bcl-2 proteins decreased (P<0.05). Compared with H₂O₂ group, the chondrocyte viability, apoptosis rate, ROS fluorescence intensity, p-p38-MAPK/p38-MAPK, and the expression of Bax protein in dihydromyricetin low concentration group, dihydromyricetin high concentration group, and NAC group decreased, the level of Col2α1 mRNA, and the expression of Col2α1 and Bcl-2 proteins increased (P<0.05). CONCLUSION Dihydromyricetin may inhibit chondrocyte apoptosis, inflammatory reaction and oxidative stress by inhibiting ROS/p38-MAPK pathway. Dihydromyricetin may be a potential drug for treating osteoarthritis.
Animals ; Chondrocytes/metabolism* ; Apoptosis/drug effects* ; Hydrogen Peroxide/toxicity* ; Osteoarthritis/physiopathology* ; Mice, Inbred C57BL ; Reactive Oxygen Species/metabolism* ; Mice ; Flavonols/pharmacology* ; p38 Mitogen-Activated Protein Kinases/genetics* ; Cell Proliferation/drug effects* ; Male ; Signal Transduction/drug effects* ; MAP Kinase Signaling System/drug effects* ; Cells, Cultured

Eight previously undescribed lanostane triterpenoids, including five nortriterpenoids with 26 carbons, ganothenoids A-E (1-5), and three lanostanoids, ganothenoids F-H (6-8), along with 24 known ones (9-32), were isolated from the fruiting bodies of Ganodrma theaecolum. The structures of the novel compounds were elucidated using comprehensive spectroscopic methods, including electronic circular dichroism (ECD) and nuclear magnetic resonance (NMR) calculations. Compounds 1-32 were assessed for their neuroprotective effects against H₂O₂-induced damage in human neuroblastoma SH-SY5Y cells, as well as their inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase. Compound 4 demonstrated the most potent neuroprotective activity against H₂O₂-induced oxidative stress by suppressing G₀/G₁ phase cell cycle arrest, reducing reactive oxygen species (ROS) levels, and inhibiting cell apoptosis through modulation of B-cell lymphoma 2 protein (Bcl-2) and Bcl-2 associated X-protein (Bax) protein expression. Compounds 26, 12, and 28 exhibited PTP1B inhibitory activities with IC₅₀ values ranging from 13.92 to 56.94 μmol·L^-1, while compound 12 alone displayed significant inhibitory effects on α-glucosidase with an IC₅₀ value of 43.56 μmol·L^-1. Additionally, enzyme kinetic analyses and molecular docking simulations were conducted for compounds 26 and 12 with PTP1B and α-glucosidase, respectively.
Humans ; Fruiting Bodies, Fungal/chemistry* ; Triterpenes/isolation & purification* ; Neuroprotective Agents/isolation & purification* ; Protein Tyrosine Phosphatase, Non-Receptor Type 1/metabolism* ; Ganoderma/chemistry* ; Apoptosis/drug effects* ; Hypoglycemic Agents/isolation & purification* ; Molecular Structure ; alpha-Glucosidases/metabolism* ; Cell Line, Tumor ; Reactive Oxygen Species/metabolism* ; Oxidative Stress/drug effects* ; Hydrogen Peroxide/toxicity* ; Molecular Docking Simulation

Thirteen novel diterpenoids, comprising seven tiglianes (walliglianes G-M, 1-7), four rhamnofolanes (wallinofolanes A-D, 8-11), and two daphnanes (wallaphnanes A and B, 12 and 13), together with two known rhamnofolane diterpenoids (euphorwallside H and euphorwallside I, 14 and 15), were isolated and characterized from Euphorbia wallichii(E. wallichii). The chemical structures of these compounds were elucidated through nuclear magnetic resonance (NMR), mass spectrometry (MS), and quantum chemical calculations. Compounds 9 and 11 demonstrated protective effects against H₂O₂-induced BV-2 microglial cell damage. Molecular docking analyses indicated that compound 9 exhibited binding affinity to the anti-oxidant-related targets HMGCR, GSTP1, and SHBG.
Euphorbia/chemistry* ; Antioxidants/isolation & purification* ; Diterpenes/isolation & purification* ; Molecular Structure ; Mice ; Molecular Docking Simulation ; Animals ; Hydrogen Peroxide/toxicity* ; Cell Line ; Microglia/drug effects*

Five undescribed sesquiterpenoids (1-5), and nine known sesquiterpenoids (6-14) were obtained from the fruits of Litsea lancilimba Merr. by LC-MS/MS molecular networking strategies. Litsemene A (1) possessed a unique 8-member ring through unexpected cyclization of the methyl group on C-10 of guaiane. Their structures were elucidated by spectroscopic techniques including IR, UV, NMR, HR-ESI-MS, and their absolute configurations were assigned by ECD calculations. All isolated sesquiterpenoids were analyzed by bioinformatics and evaluated for their neuroprotective effects against H₂O₂-induced injury in human neuroblastoma SH-SY5Y cells.
Chromatography, Liquid ; Humans ; Hydrogen Peroxide/toxicity* ; Litsea ; Molecular Structure ; Neuroblastoma/drug therapy* ; Neuroprotective Agents/pharmacology* ; Sesquiterpenes/chemistry* ; Tandem Mass Spectrometry

NEDDylation has been shown to participate in the DNA damage pathway, but the substrates of neural precursor cell expressed developmentally downregulated 8 (NEDD8) and the roles of NEDDylation involved in the DNA damage response (DDR) are largely unknown. Translesion synthesis (TLS) is a damage-tolerance mechanism, in which RAD18/RAD6-mediated monoubiquitinated proliferating cell nuclear antigen (PCNA) promotes recruitment of polymerase η (polη) to bypass lesions. Here we identify PCNA as a substrate of NEDD8, and show that E3 ligase RAD18-catalyzed PCNA NEDDylation antagonizes its ubiquitination. In addition, NEDP1 acts as the deNEDDylase of PCNA, and NEDP1 deletion enhances PCNA NEDDylation but reduces its ubiquitination. In response to HO stimulation, NEDP1 disassociates from PCNA and RAD18-dependent PCNA NEDDylation increases markedly after its ubiquitination. Impairment of NEDDylation by Ubc12 knockout enhances PCNA ubiquitination and promotes PCNA-polη interaction, while up-regulation of NEDDylation by NEDD8 overexpression or NEDP1 deletion reduces the excessive accumulation of ubiquitinated PCNA, thus inhibits PCNA-polη interaction and blocks polη foci formation. Moreover, Ubc12 knockout decreases cell sensitivity to HO-induced oxidative stress, but NEDP1 deletion aggravates this sensitivity. Collectively, our study elucidates the important role of NEDDylation in the DDR as a modulator of PCNA monoubiquitination and polη recruitment.
DNA Damage ; drug effects ; DNA Repair ; genetics ; DNA Replication ; genetics ; DNA-Binding Proteins ; genetics ; DNA-Directed DNA Polymerase ; genetics ; Endopeptidases ; genetics ; Gene Knockout Techniques ; Humans ; Hydrogen Peroxide ; toxicity ; NEDD8 Protein ; genetics ; Oxidative Stress ; genetics ; Proliferating Cell Nuclear Antigen ; genetics ; Ubiquitin-Conjugating Enzymes ; genetics ; Ubiquitin-Protein Ligases ; genetics ; Ubiquitination ; genetics ; Ultraviolet Rays

Caesalpinia sappan L., belonging to the family Leguminosae, is a medicinal plant that is distributed in Southeast Asia. The dried heartwood of this plant is used as a traditional ingredient of food, red dyes, and folk medicines in the treatment of diarrhea, dysentery, tuberculosis, skin infections, and inflammation. Brazilin is the major active compound, which has exhibited various pharmacological effects, including anti-platelet activity, anti-hepatotoxicity, induction of immunological tolerance, and anti-inflammatory and antioxidant activities. The present study aimed to evaluate the antioxidant activity and expression of antioxidant enzymes of C. sappan L. extract and its major compound, brazilin, in human epidermal keratinocytes exposed to UVA irradiation. Our results indicated that C. sappan L. extract reduced UVA-induced HO production via GPX7 activation. Moreover, brazilin exhibited antioxidant effects that were similar to those of C. sappan L. via glutathione peroxidase 7 (GPX7), suggesting that C. sappan L. extract and its natural compound represent potential treatments for oxidative stress-induced photoaging of skin.
Antioxidants ; pharmacology ; Benzopyrans ; pharmacology ; Caesalpinia ; chemistry ; Humans ; Hydrogen Peroxide ; toxicity ; Keratinocytes ; cytology ; drug effects ; enzymology ; radiation effects ; Oxidative Stress ; drug effects ; radiation effects ; Peroxidases ; genetics ; metabolism ; Plant Extracts ; pharmacology ; Protective Agents ; pharmacology ; Ultraviolet Rays

Oxidative stress, a predominant cause of apoptosis cascades triggered in neurodegenerative disorders, has been regarded as a critical inducement in the pathogenesis of Alzheimer's disease (AD). Gou Teng-San (GTS) is a traditional Chinese herbs preparation commonly utilized to alleviate cognitive dysfunction and psychological symptoms of patients with dementia. The present study aimed to investigate the protective effects of GTS40, an active fraction of GTS, on HO-induced oxidative damage and identify the potential active ingredients. Our results revealed that GTS40 exhibited radical scavenging activity, elevated cell viability, decreased the levels of intracellular reactive oxygen species (ROS), and stabilized mitochondrial transmembrane potential (MMP) in HO-treated PC12 cells. In addition, GTS40 blocked the apoptotic cascade by reversing the imbalance of Bcl-2/Bax and inhibiting the activity of caspase-3. Furthermore, an HPLC-QTOFMS method was developed to characterize major chemical constituents in GTS40. Our results revealed twenty-seven identified or tentatively characterized compounds through comparing their retention time (t) and MS spectra with reference standards. These results suggested that GTS40 was a promising active fraction that may be beneficial in the prevention and treatment of oxidative stress-mediated neurodegenerative disorders.
Animals ; Antioxidants ; analysis ; pharmacology ; Apoptosis ; drug effects ; Caspase 3 ; genetics ; metabolism ; Drugs, Chinese Herbal ; analysis ; pharmacology ; Hydrogen Peroxide ; toxicity ; Neurons ; cytology ; drug effects ; metabolism ; Neuroprotective Agents ; analysis ; pharmacology ; Oxidative Stress ; drug effects ; PC12 Cells ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Rats ; Reactive Oxygen Species ; metabolism

The fruits of Paulownia catalpifolia Gong Tong are used as a Chinese folk herbal medicine for the treatment of enteritis, tonsillitis, bronchitis, and dysentery, etc. Our previous study has identified new C-geranylated flavanones with obvious anti-proliferative effects in lung cancer A549 cells. In the present study, a new C-geranylated flavone, paucatalinone C (1) and five known C-geranylated flavanones (2-6) were isolated. In addition, a total of 34 C-geranylated flavonoids were detected by HPLC-DAD-ESI-MS/MS coupling techniques from the CHCl extract of P. catalpifolia. Futhermore, anti-aging effects of isolated compounds were evaluated in vitro with premature senescent 2BS cells induced by HO. Phytochemical results indicated that P. catalpifolia was a natural resource of abundant C-geranylated flavonoids. Diplacone (3) and paucatalinone A (5) were the potent anti-aging agents in the premature senescent 2BS cells induced by HO and the C-geranyl substituent may be an important factor because of its lipophilic character.
Aging ; drug effects ; Cell Line ; Chromatography, High Pressure Liquid ; Flavonoids ; chemistry ; isolation & purification ; pharmacology ; Fruit ; chemistry ; Humans ; Hydrogen Peroxide ; toxicity ; Magnoliopsida ; chemistry ; Molecular Structure ; Plant Extracts ; chemistry ; isolation & purification ; pharmacology ; Tandem Mass Spectrometry

Neurofibrillary pathology of abnormally hyperphosphorylated tau is a hallmark of Alzheimer's disease (AD) and other tauopathies. Phosphatidylinositol 3-kinase (PI3K)/Akt/glycogen synthase kinase-3 beta (GSK-3β) signaling pathway is pivotal for tau phosphorylation. Inhibition of soluble epoxide hydrolase (sEH) metabolism has been shown to effectively increase the accumulation of epoxyeicosatrienoic acids (EETs), which are cytochrome P450 metabolites of arachidonic acid and have been demonstrated to have neuroprotective effects. However, little is known about the role of sEH in tau phosphorylation. The present study investigated the role of a sEH inhibitor, 1-(1-propanoylpiperidin-4-yl)-3-[4-(trifluoromethoxy)phenyl] urea (TPPU), on HO-induced tau phosphorylation and the underlying signaling pathway in human embryonic kidney 293 (HEK293)/Tau cells. We found that the cell viability was increased after TPPU treatment compared to control in oxidative stress. Western blotting and immunofluorescence results showed that the levels of phosphorylated tau at Thr231 and Ser396 sites were increased in HO-treated cells but dropped to normal levels after TPPU administration. HOinduced an obvious decreased phosphorylation of GSK-3β at Ser9, an inactive form of GSK-3β, while there were no changes of phosphorylation of GSK-3β at Tyr216. TPPU pretreatment maintained GSK-3β Ser 9 phosphorylation. Moreover, Western blotting results showed that TPPU upregulated the expression of p-Akt. The protective effects of TPPU were found to be inhibited by wortmannin (WT, a specific PI3K inhibitor). In conclusion, these results suggested that the protective effect of TPPU on HO-induced oxidative stress is associated with PI3K/Akt/GSK-3β pathway.
Cell Survival ; drug effects ; Enzyme Inhibitors ; pharmacology ; Glycogen Synthase Kinase 3 beta ; metabolism ; HEK293 Cells ; Humans ; Hydrogen Peroxide ; toxicity ; Oxidative Stress ; Phenylurea Compounds ; pharmacology ; Phosphatidylinositol 3-Kinases ; metabolism ; Phosphorylation ; Piperidines ; pharmacology ; Protein Processing, Post-Translational ; Proto-Oncogene Proteins c-akt ; metabolism ; Signal Transduction ; tau Proteins ; metabolism

OBJECTIVEWe evaluate the effects of Thymus algeriensis (TEO) against hydrogen peroxide (H2O2) toxicity on body and testis weight, testis sperm count, testis lipid peroxidation, and antioxidant enzyme activities in rats.

METHODSRats were treated with low (LD) and high dose (HD) of H2O2 (0.1 and 1 mmol/L) in the presence or absence of TEO (150 mg/kg).

RESULTSThe results exhibited a significant decrease in body weight and testis weight, in total sperm number decrease (P<0.05), sperm motility and percentage of sperm viability, leading to complete arrest, in sperm flagellar beat frequency by the gavage of 1 mmol/L H2O2 compared to controls. The administration of H2O2 resulted in a significant reduction in testis GSH, GPx, CAT, SOD, and GST activity and significant increase (P<0.05) in MDA concentration compared with the untreated control animals. TEO pre-treatment protected testis from the H2O2 generated oxidative stress. These results were confirmed by histological architecture examinations.

CONCLUSIONH2O2 has the ability to alter the sperm function, characteristics and development of testis. However, TEO is an efficient natural agent, which can prevent the testis from H2O2-induced oxidative damage in rats.

Animals ; Hydrogen Peroxide ; toxicity ; Male ; Oxidative Stress ; Plant Extracts ; pharmacology ; Rats ; Rats, Wistar ; Testis ; drug effects ; Thymus Plant ; chemistry