Titanium Dioxide Inhibits Hippocampal Neuronal Synapse Growth Through the Brain-Derived Neurotrophic Factor-Tyrosine Kinase Receptor B Signaling Pathway

Nanoparticulate titanium dioxide (nano-TiO2) is a commonly used nanoparticle material and has been widely used in the fields of medicine, cosmetics, construction, and environmental protection. Numerous studies have demonstrated that nano-TiO2 has toxic effects on neuronal development, which lead to defects in learning and memory functions. However, it is still unclear whether nano-TiO2 inhibits the development of synapse and the underlying molecular mechanism is still unknown. In this study, nano-TiO2 was administered to rat primary hippocampal neurons for 24 h to investigate the underlying molecular mechanisms behind the inhibition of neuronal synaptic development by nano-TiO2. We used hippocampal neurons as a model to study the effect of nano-TiO2 on synaptic development. Our results demonstrated that dendritic development that represented synaptic plasticity in hippocampal neurons was significantly inhibited in a concentration-dependent manner after exposure to nano-TiO2 for 24 h. Experiments with varying concentrations of nano-TiO2 (5, 15, and 30 g/mL) indicated that the apoptotic rate of hippocampal neurons increased, development of neuronal synapses were inhibited, and synaptic densities decreased by 24.29%, 54.29%, and 72.86%, respectively, in post-treatment with nano-TiO2. Furthermore, the results indicated that the expressions of Synapsin I (SYN I) and postsynaptic density 95 (PSD95) in neuron synapse were also significantly inhibited, particularly SYN I decreased by 18.43%, 37.2%, and 51.6%, and PSD95 decreased by 16.02%, 24.06%, and 38.74% after treatment with varying concentrations of nano-TiO2, respectively. In addition, experiments to assess the BDNF-TrkB signaling pathway indicated that nano-TiO2 inhibited the expressions of key proteins in the downstream MEK/ERK and PI3K/Akt signaling pathways by inhibiting the expression of BDNF. With concentrations of nano-TiO2 at 5, 15, and 30 μg/mL, the expression of BDNF decreased by 22.64%, 33.3%, and 53.58% compared with the control group. Further, the expression ratios of downstream key proteins p-CREB/CREB decreased by 3.03%, 18.11%, and 30.57%; p-ERK1/2/ERK1/2 ratios decreased by 19.11%, 28.82%, and 58.09%, and p-Akt1/Akt1 ratios decreased by 1.92%, 27.79%, and 41.33%, respectively. These results demonstrated that nano-TiO2 inhibited the normal function of the BDNF-TrkB signaling pathway, which is closely related to neuronal synapse. Thus, it can be hypothesized that the inhibition of neuronal synaptic growth by nano-TiO2 may be related to the inhibition of BDNF-TrkB signaling pathway.

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Glycinin-induced porcine IPEC-J2 cells damage via the NF-κB/MAPK signaling pathway

10.21203/rs.3.rs-16881/v2 ◽

2020 ◽

Author(s):

Chenglu Peng ◽

Zhifeng Sun ◽

Lei Wang ◽

Yingshuang Shu ◽

Mengchu He ◽

...

Keyword(s):

Signaling Pathway ◽

Intestinal Barrier ◽

Mapk Signaling ◽

Mapk Signaling Pathway ◽

Control Group ◽

Epithelial Cell Line ◽

Pyrrolidine Dithiocarbamate ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Nitric Oxide Synthase Inhibitor

Abstract Background: Glycinin, a protein found in soybean, is a human and animal allergen that causes damage to the intestinal barrier. However, its mechanisms of action remain unclear. Therefore, in this study, the intestinal porcine epithelial cell line IPEC-J2 was used to evaluate the effect of glycinin concentration on the intestinal epithelium and identify the related signaling pathways. Results: IPEC-J2 cells were divided into seven treatment groups and a control group; the cells were treated for 24 h with 1, 5, or 10 mg/mL glycinin or with 5 mg/mL glycinin after 30 min of pre-treatment with 1 μmol/L nuclear factor-kappa B (NF-κB) inhibitor (pyrrolidine dithiocarbamate), inducible nitric oxide synthase inhibitor ( N -ω-nitro-l-arginine methyl ester), Jun N-terminal kinase (JNK) inhibitor (SP600125), or p38 inhibitor (SB202190). A series of molecular and biochemical experiments revealed that the levels of NF-κB, p38, and JNK, as well as their downstream proteins, were increased after treatment compared to those in the control group. Conclusion: Glycinin damaged IPEC-J2 cells in a concentration-dependent manner via the NF-κB/MAPK signaling pathway.

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The Role of CD39/CD73/Ado/A2AR Axis and HIF-1α in Chronic Lymphocytic Leukemia

Blood ◽

10.1182/blood-2018-99-115732 ◽

2018 ◽

Vol 132 (Supplement 1) ◽

pp. 4406-4406 ◽

Cited By ~ 1

Author(s):

Yiqing Cai ◽

Lili Feng ◽

Dai Yuan ◽

Qian Wang ◽

Xin Wang

Keyword(s):

Protein Expression ◽

Western Blot ◽

Molecular Mechanisms ◽

Conflicts Of Interest ◽

Lymphocytic Leukemia ◽

Control Group ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Protein Expressions ◽

A2ar Agonist

Abstract Introduction: CD39/CD73/ADO/A2A system plays important roles in tumor growth and therapy. Extracellular adenosine (ADO) receptor A2A (A2AR) is the dominant receptor expressed on chronic lymphocytic leukemia (CLL) cells. ADO has been shown to protect CLL cells from spontaneous and drug-induced apoptosis through A2AR activation. Overexpression of hypoxia inducible factor-1α (HIF-1α), an important mediator controlling the expression of a wide variety of apoptotic genes, has been observed in bone marrow leukemic cells from CLL patients. However, the reciprocal action of A2AR and HIF-1α in CLL remains elusive. This study was aimed to explore the molecular mechanisms underlying the relationship between A2AR activation and HIF-1α in CLL. Materials and Methods: Peripheral blood (PB) and bone marrow (BM) samples were collected from 30 healthy volunteers (control) and 20 patients who were diagnosed with CLL for the first time at the Hematology Department in our hospital. CD39/CD73/ADO/A2AR axis-related protein and HIF-1α protein expressions in CLL PB and BM tissues were examined by Western-blot. CD39, CD73, A2AR and HIF-1α expression on CLL cells were also determined by FACS. CLL cell line (Lym-2) was purchased from ATCC and incubated in DMEM medium supplemented with 10% FBS. The protein expressions of CD39, CD73 and A2AR on Lym-2 cells were confirmed by Western-blot. To study the impacts of A2AR activation and inactivation on CLL cells, CLL cells were treated with A2AR agonist CGS21680 or antagonist SCH58261, followed by determination of cell proliferation and HIF-1α protein expression. Results: The protein expressions of CD39, CD73, A2AR and HIF-1α were higher in CLL group than those in control group (BM: CD39 1.471 vs 0.926, CD73 1.097 vs 0.489, A2AR 1.139 vs 0.342 and HIF-1α 0.940 vs 0.362, P<0.05 Figure 1A; PB : CD39 1.809 vs 1.331, CD73 1.039 vs 0.653, A2AR 1.738 vs 1.119 and HIF-1α 1.336 vs 1.010, P<0.05 Figure 1B). Moreover, CD73 and HIF-1α protein expression was found to have relationship with disease stage. Patients who belonged to stage IV (Rai) and stage B/C (Binet) exhibited higher levels of CD73 and HIF-1α than patients who belonged to stage I to III (Rai) and stage A (Binet) . Data from FACS analysis showed that the proportion of CD39+CLL cells was higher than CD73+CLL cells and HIF-1α+CLL cells (P<0.05, Figure 2A). When compared to control group, the proportions of CD39+cells and CD73+ cells were significant higher in CLL group (Figure 2B). Western-blot results showed that Lym-2 cells expressed CD39, CD73 and A2AR simultaneously (Figure 3A). The results from CLL cells and A2AR agonist/antagonist incubation showed that when CGS21680 concentration was of ≥ 10uM, cell proliferation was promoted obviously (Figure 3B). On the contrary, SCH58261 could inhibit CLL cells proliferation when its concentration was of ≥5uM at a concentration dependent manner (Figure 3C). Moreover, HIF-1α protein expression was also affected by A2AR agonist at a concentration dependent manner(0uM 0.851, 10uM 1.116, 20uM 1.420, 50uM 1.41, Figure 3D). Conclusion: Our study showed that ADO produced by CD39 and CD73 could affect CLL cells proliferation and HIF-1α expression through A2AR-mediated mechanisms. The exploration of the molecular mechanisms underlying the relationship between A2AR activation and HIF-1α could help us to find a novel approach to CLL therapy. Disclosures: No relevant conflicts of interest to declare. Disclosures No relevant conflicts of interest to declare.

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The Anti-Atherogenic Properties of Sesamin are Mediated via Improved Macrophage Cholesterol Efflux Through PPARγ1-LXRα and MAPK Signaling

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000195 ◽

2014 ◽

Vol 84 (1-2) ◽

pp. 79-91 ◽

Cited By ~ 7

Author(s):

Amin F. Majdalawieh ◽

Hyo-Sung Ro

Keyword(s):

Cholesterol Efflux ◽

Transcriptional Activity ◽

Molecular Mechanisms ◽

Foam Cell ◽

Mapk Signaling ◽

Luciferase Reporter ◽

Foam Cell Formation ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Macrophage Cholesterol Efflux

Background: Foam cell formation resulting from disrupted macrophage cholesterol efflux, which is triggered by PPARγ1 and LXRα, is a hallmark of atherosclerosis. Sesamin and sesame oil exert anti-atherogenic effects in vivo. However, the exact molecular mechanisms underlying such effects are not fully understood. Aim: This study examines the potential effects of sesamin (0, 25, 50, 75, 100 μM) on PPARγ1 and LXRα expression and transcriptional activity as well as macrophage cholesterol efflux. Methods: PPARγ1 and LXRα expression and transcriptional activity are assessed by luciferase reporter assays. Macrophage cholesterol efflux is evaluated by ApoAI-specific cholesterol efflux assays. Results: The 50 μM, 75 μM, and 100 μM concentrations of sesamin up-regulated the expression of PPARγ1 (p< 0.001, p < 0.001, p < 0.001, respectively) and LXRα (p = 0.002, p < 0.001, p < 0.001, respectively) in a concentration-dependent manner. Moreover, 75 μM and 100 μM concentrations of sesamin led to 5.2-fold (p < 0.001) and 6.0-fold (p<0.001) increases in PPAR transcriptional activity and 3.9-fold (p< 0.001) and 4.2-fold (p < 0.001) increases in LXR transcriptional activity, respectively, in a concentration- and time-dependent manner via MAPK signaling. Consistently, 50 μM, 75 μM, and 100 μM concentrations of sesamin improved macrophage cholesterol efflux by 2.7-fold (p < 0.001), 4.2-fold (p < 0.001), and 4.2-fold (p < 0.001), respectively, via MAPK signaling. Conclusion: Our findings shed light on the molecular mechanism(s) underlying sesamins anti-atherogenic effects, which seem to be due, at least in part, to its ability to up-regulate PPARγ1 and LXRα expression and transcriptional activity, improving macrophage cholesterol efflux. We anticipate that sesamin may be used as a therapeutic agent for treating atherosclerosis.

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Pisosterol Induces G2/M Cell Cycle Arrest and Apoptosis via the ATM/ATR Signaling Pathway in Human Glioma Cells

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520620666200203160117 ◽

2020 ◽

Vol 20 (6) ◽

pp. 734-750

Author(s):

Wallax A.S. Ferreira ◽

Rommel R. Burbano ◽

Claudia do Ó. Pessoa ◽

Maria L. Harada ◽

Bárbara do Nascimento Borges ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Signaling Pathway ◽

Glioma Cell ◽

Molecular Mechanisms ◽

Glioma Cells ◽

Dependent Manner ◽

M Cell ◽

Trypan Blue Exclusion ◽

Cycle Arrest

Background: Pisosterol, a triterpene derived from Pisolithus tinctorius, exhibits potential antitumor activity in various malignancies. However, the molecular mechanisms that mediate the pisosterol-specific effects on glioma cells remain unknown. Objective: This study aimed to evaluate the antitumoral effects of pisosterol on glioma cell lines. Methods: The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and trypan blue exclusion assays were used to evaluate the effect of pisosterol on cell proliferation and viability in glioma cells. The effect of pisosterol on the distribution of the cells in the cell cycle was performed by flow cytometry. The expression and methylation pattern of the promoter region of MYC, ATM, BCL2, BMI1, CASP3, CDK1, CDKN1A, CDKN2A, CDKN2B, CHEK1, MDM2, p14ARF and TP53 was analyzed by RT-qPCR, western blotting and bisulfite sequencing PCR (BSP-PCR). Results: Here, it has been reported that pisosterol markedly induced G2/M arrest and apoptosis and decreased the cell viability and proliferation potential of glioma cells in a dose-dependent manner by increasing the expression of ATM, CASP3, CDK1, CDKN1A, CDKN2A, CDKN2B, CHEK1, p14ARF and TP53 and decreasing the expression of MYC, BCL2, BMI1 and MDM2. Pisosterol also triggered both caspase-independent and caspase-dependent apoptotic pathways by regulating the expression of Bcl-2 and activating caspase-3 and p53. Conclusions: It has been, for the first time, confirmed that the ATM/ATR signaling pathway is a critical mechanism for G2/M arrest in pisosterol-induced glioma cell cycle arrest and suggests that this compound might be a promising anticancer candidate for further investigation.

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Evaluation of MACF1-regulatory non-coding RNA as a potential therapeutic target in Colorectal Cancer

QJM ◽

10.1093/qjmed/hcab088.011 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Rowaida Mohammed Reda M. M Aboushahba ◽

Fayda Ibrahim Abdel Motaleb ◽

Ahmed Abdel Aziz Abou-Zeid ◽

Enas Samir Nabil ◽

Dalia Abdel-Wahab Mohamed ◽

...

Keyword(s):

Colorectal Cancer ◽

Cell Proliferation ◽

Wnt Signaling ◽

Cell Line ◽

Signaling Pathway ◽

Therapeutic Target ◽

Molecular Mechanisms ◽

Wnt Signaling Pathway ◽

Control Group ◽

Potential Therapeutic Target

ABSTRACT Colorectal cancer (CRC) is one of the leading causes of cancer-related deaths world-wide. There is an increasing need for the identification of novel biomarkers/targets for early diagnosis and for the development of novel chemopreventive and therapeutic agents for CRC. Recently, MACF1 gene has emerged as a potential therapeutic target in cancer as it involved in processes critical for tumor cell proliferation, invasion and metastasis. It is suggested that MACF1 may function in cancers through Wnt signaling. MiR-34a is a well-known tumor suppressor miRNA.miR-34a targets MACF1 gene as a part of the wnt signaling pathway. In this study, 40 colonic tissues were collected from CRC patients (20) and control subjects (20). miR-34a-5p was assessed by real time PCR in all study groups. The results showed highly significant decrease (P < 0.01) in miR-34a relative expression in the CRC group (median RQ 0.13) when compared to the benign group (median RQ 5.3) and the healthy control group (median RQ 19.63). miR-34a mimic and inhibitor were transfected in CaCo-2 cell line and proliferation was assessed. The transfection of the cell line with miR-34a mimic decreased cell proliferation. Our study suggests that miR-34a-5p targets MACF1 gene as a part of the wnt signaling pathway leading to the involvement in the molecular mechanisms of CRC development and progression.

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Sequestration of erythrocytes infected with Plasmodium berghei ANKA in BALB/c mice treated with goat bile

Qanun Medika - Medical Journal Faculty of Medicine Muhammadiyah Surabaya ◽

10.30651/jqm.v4i2.3539 ◽

2020 ◽

Vol 4 (2) ◽

pp. 179

Author(s):

Kartika Arum Wardani ◽

Kholida Nur Aini ◽

Heny Arwati ◽

Willy Sandhika

Keyword(s):

Plasmodium Berghei ◽

Antimalarial Activity ◽

Negative Control ◽

Control Group ◽

Dependent Manner ◽

Plasmodium Berghei Anka ◽

Concentration Dependent Manner ◽

Control Group Design ◽

Bile Concentration

Abstract Sequestration of Plasmodium berghei ANKA-infected erythrocytes occurs in BALB/c mice as characteristic of Plasmodium falciparum infection in humans. Animals’ bile has been widely used for centuries in Traditional Chinese Medicine. Goat bile has been used in healing infectious and non-infectious diseases; however, no report on the use of goat bile against malaria infection and sequestration. The purpose of this study was to analyze the correlation between parasitemia and sequestration in the liver of P.berghei ANKA-infected BALB/c mice treated with goat bile. This research was an in vivo experimental study using the post-test control group design. The male BALB/c mice aged ± 6 weeks, body weight 20-25 g were used. The mice were divided into five groups where Group 1-3 were mice treated with goat bile 25%, 50%, and 100%, respectively. Group 4-5 were negative (sterile water) and positive controls (DHP). Parasitemia was observed daily from each mouse and the number of sequestered infected erythrocytes on the endothelium of sinusoids. The data were analyzed using t independent test. Antimalarial activity of goat bile was shown by the lower parasitemia in goat bile-treated mice compared with the negative control. The average number of sequestration was goat bile concentration-dependent manner. The higher the concentration, the lower the number of sequestration. Sequestration was correlated with parasitemia (p=0,0001). Sequestration of P.berghei ANKA-infected erythrocytes correlated with parasitemia, and was goat bile concentration-dependent manner. Keywords: Malaria, parasitemia, sequestration, goat bileCorrespondence: [email protected]

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Live Cell FRET Imaging Reveals Amyloid β-Peptide Oligomerization in Hippocampal Neurons

10.20944/preprints202103.0426.v1 ◽

2021 ◽

Author(s):

Yang Gao ◽

Stefan Wennmalm ◽

Bengt Winblad ◽

Sophia Schedin-Weiss ◽

Lars Tjernberg

Keyword(s):

Hippocampal Neurons ◽

Resonance Energy Transfer ◽

Amyloid Β ◽

Resonance Energy ◽

Live Cell ◽

Amyloid Β Peptide ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Late Endosomes ◽

Aβ Oligomerization

Amyloid β-peptide (Aβ) oligomerization is believed to contribute to the neuronal dysfunction in Alzheimer disease (AD). Despite decades of research, many details of Aβ oligomerization in neurons still need to be revealed. Förster Resonance Energy Transfer (FRET) is a simple but effective way to study molecular interactions. Here we use a confocal microscope with a sensitive Airyscan detector for FRET detection. By live cell FRET imaging, we detect Aβ42 oligomerization in primary neurons. The neurons were incubated with fluorescently labelled Aβ42 in the cell culture medium for 24 hours. Aβ42 were internalized and oligomerized into the lysosomes/late endosomes in a concentration-dependent manner. Both the cellular uptake and intracellular oligomerization of Aβ42 were significantly higher than for Aβ40. These findings provide a better understanding of Aβ42 oligomerization in neurons.

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Relaxant effect of quercetin on rabbit isolated bladder smooth muscles contractions

Journal of Herbmed Pharmacology ◽

10.34172/jhp.2021.05 ◽

2020 ◽

Vol 10 (1) ◽

pp. 61-67

Author(s):

Hassan Sadraei ◽

Sabihe Tabesh

Keyword(s):

Smooth Muscles ◽

Electrical Field Stimulation ◽

Negative Control ◽

Flavonoid Compound ◽

Drug Candidate ◽

Control Group ◽

Organ Bath ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Relaxant Effect

Introduction: Quercetin is a flavonoid compound found in many medicinal plants. Antispasmodic effect of quercetin has been reported in ileum and uterus smooth muscles but not in bladder. Therefore, the objective of this research was to investigate relaxant effect of quercetin in rabbit isolated bladder. Methods: Male rabbit was asphyxiated with carbon dioxide and then sacrificed. The whole bladder was dissected out and placed in oxygenated Tyrode’s solution. Isolated bladder was cut into longitudinal strips and placed in an organ bath for contraction studies. Contractions were induced with KCl (20mM), acetylcholine (5μM) and electrical field stimulation (EFS). Full inhibitory concentration–response curve was constructed for quercetin following addition of above spasmogens. Quercetin was added into the organ bath with 2 fold increments in concentration until maximum response was achieved. Nifedipine was used as positive control group and equivalent volume of quercetin vehicle (water + DMSO) was used as negative control group.Results: Quercetin (4 μg/mL to 640 μg/mL) in a concentration dependent manner inhibited isolated bladder strips contracted by KCl (IC50=159±25 μg/mL), acetylcholine (IC50=43±9.1 μg/mL) and EFS (IC50=38±9.3 μg/mL). In the highest used concentration, quercetin completely removed contractile responses to KCl, acetylcholine and electrical filed stimulation (EFS). Nifedipine totally inhibited KCl response (IC50=115±36 ng/mL) but only partially inhibited acetylcholine and EFS responses. Conclusion: These results confirm the relaxant effect of quercetin on rabbit bladder and if similar effects are seen in human studies, then quercetin would be a suitable drug candidate to be investigated for bladder incontinence.

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Methanol Extract of Mongolian Iris bungei Maxim. Stimulates 3T3-L1 Adipocyte Differentiation

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2021.19160 ◽

2021 ◽

Vol 21 (7) ◽

pp. 3943-3949

Author(s):

Jaegoo Yeon ◽

Sung-Suk Suh ◽

Ui-Joung Youn ◽

Badamtsetseg Bazarragchaa ◽

Ganbold Enebish ◽

...

Keyword(s):

Bacterial Infections ◽

Fatty Acid Synthase ◽

Molecular Mechanisms ◽

Adipocyte Differentiation ◽

Methanol Extract ◽

Regulatory Element ◽

Peroxisome Proliferator ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Peroxisome Proliferator Activated Receptor

Iris bungei Maxim. (IB), which is native to China and Mongolia, is used as a traditional medicine for conditions such as inflammation, cancer, and bacterial infections. However, the effects of Iris bungei Maxim. on adipocyte differentiation have not been studied. In the present study, we first demonstrated the molecular mechanisms underlying the adipogenic activity of the methanol extract of Mongolian I. bungei Maxim. (IB). IB significantly enhanced intracellular lipid accumulation and adipocyte differentiation in 3T3-L1 preadipocytes in a concentration-dependent manner. Moreover, IB markedly stimulated the expression of genes related to adipogenesis such as peroxisome proliferator-activated receptor γ, adiponectin, and aP2. In addition, we also observed that IB induces lipogenic genes such as fatty acid synthase, sterol regulatory element binding protein 1c, stearoyl-CoA desaturase, and acetyl-CoA carboxylase. Interestingly IB regulated adipocyte differentiation in both the early and middle stages. Taken together, these adipogenic and lipogenic effects of IB suggest its efficacy for the prevention and/or treatment of type 2 diabetes.

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Betulinic Acid Suppresses Ovarian Cancer Cell Proliferation through Induction of Apoptosis

Biomolecules ◽

10.3390/biom9070257 ◽

2019 ◽

Vol 9 (7) ◽

pp. 257 ◽

Cited By ~ 1

Author(s):

Dahae Lee ◽

Seoung Rak Lee ◽

Ki Sung Kang ◽

Yuri Ko ◽

Changhyun Pang ◽

...

Keyword(s):

Ovarian Cancer ◽

Cancer Cell ◽

Betulinic Acid ◽

Molecular Mechanisms ◽

Underlying Mechanism ◽

Nuclear Staining ◽

Dependent Manner ◽

Meoh Extract ◽

Concentration Dependent Manner ◽

Induction Of Apoptosis

Ovarian cancer is one of the leading causes of cancer deaths worldwide in women, and the most malignant cancer among the different gynecological cancers. In this study, we explored potentially anticancer compounds from Cornus walteri (Cornaceae), the MeOH extract of which has been reported to show considerable cytotoxicity against several cancer cell lines. Phytochemical investigations of the MeOH extract of the stem and stem bark of C. walteri by extensive application of chromatographic techniques resulted in the isolation of 14 compounds (1–14). The isolated compounds were evaluated for inhibitory effects on the viability of A2780 human ovarian carcinoma cells and the underlying molecular mechanisms were investigated. An 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was employed to assess the anticancer effects of compounds 1–14 on A2780 cells, which showed that compound 11 (betulinic acid) reduced the viability of these cells in a concentration-dependent manner and had an half maximal (50%) inhibitory concentration (IC50) of 44.47 μM at 24 h. Nuclear staining and image-based cytometric assay were carried out to detect the induction of apoptosis by betulinic acid. Betulinic acid significantly increased the condensation of nuclei and the percentage of apoptotic cells in a concentration-dependent manner in A2780 cells. Western blot analysis was performed to investigate the underlying mechanism of apoptosis. The results indicated that the expression levels of cleaved caspase-8, -3, -9, and Bax were increased in A2780 cells treated with betulinic acid, whereas those of Bcl-2 were decreased. Thus, we provide the experimental evidence that betulinic acid can induce apoptosis in A2780 cells through both mitochondria-dependent and -independent pathways and suggest the potential use of betulinic acid in the development of novel chemotherapeutics for ovarian cancer therapy.

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