Scutellaria litwinowii induces apoptosis through both extrinsic and intrinsic apoptotic pathways in human promyelocytic leukemia cells

Evaluating Antibiofilm, Cytotoxic and Apoptotic Activities of Scutellaria brevibracteata subsp. brevibracteata Essential Oil

Essential oils have many important biological properties, including antibacterial and antibiofilm activities. These unique properties make, essential oils good alternatives to synthetic chemical drugs, which have many side effects. In this study, we aimed to determine the chemical composition and biological activity of the essential oil obtained from Scutellaria brevibracteata subsp. brevibracteata. Specifically, its antibiofilm activity against Pseudomonas aeruginosa PAO1 and Staphylococcus aureus ATCC 29213 biofilms using XTT assay. Cytotoxic and apoptotic properties of the essential oil were investigated in human lung cancer cells (A540 and H1299) using MTT assay, Annexin V-FITC and propidium iodide staining and q-PCR. Thirty-two different compounds were identified from the essential oil, of which elemol (20.42 %), γ-eudesmol (20.12 %) and β-eudesmol (14.85 %) were the main components. The essential oil was more effective against P. aeruginosa PAO1 biofilm (79 %) than S. aureus ATCC 29213 biofilm (27 %). The specific activity of the essential oil against P. aeruginosa biofilm may be related to its high terpene contents. In addition, the essential oil showed high cytotoxic activity towards A549 (IC50 9.09 μg/ml) and H1299 (IC50 55.04 μg/ml) cell lines, inducing apoptosis in these cancer cells. These results demonstrate the antibiofilm and anticancer activities of S. brevibracteata subsp. brevibracteata essential oil.

12-Epi-Napelline Inhibits Leukemia Cell Proliferation via the PI3K/AKT Signaling Pathway In Vitro and In Vivo

This study aimed to investigate the inhibitory effect of 12-epi-napelline on leukemia cells and its possible mechanisms. The inhibitory effects of 12-epi-napelline on K-562 and HL-60 cells were evaluated using the CCK-8 assay, cell cycle arrest and apoptosis were detected by flow cytometry, and the expression of related proteins was measured by western blot. A K-562 tumor model was established to evaluate the antitumor effect of 12-epi-napelline in vivo. A reduction in leukemia cell viability was observed after treatment with 12-epi-napelline. It was determined that the cell cycle was arrested in the G0/G1 phase, and the cell apoptosis rate was increased. Moreover, caspase-3 and Bcl-2 were downregulated, whereas cleaved caspase-3 and caspase-9 were upregulated. Further study revealed that 12-epi-napelline could suppress the expression of PI3K, AKT, p-AKT, and mTOR. Insulin-like growth factor 1 (IGF-1) attenuated 12-epi-napelline-induced apoptosis and ameliorated the repression of PI3K, AKT, p-AKT, and mTOR by 12-epi-napelline. Animal experiments clearly showed that 12-epi-napelline inhibited tumor growth. In conclusion, 12-epi-napelline restrained leukemia cell proliferation by suppressing the PI3K/AKT/mTOR pathway in vitro and in vivo.

Scutellaria: Debates on the anticancer property

The widespread use of plants as accessible anticancer agents leads to the identification of many natural source chemotherapeutic agents. Scutellaria one of the popular genus of flowering plants has been used for various human illnesses for thousands of years. Scutellaria has anti-metastatic, anti-proliferative, anti-invasion, anti-angiogenic and apoptosis effects in vitro as well as in vivo. Despite numerous reports on the cytotoxic-antitumor activity of the plant, there are still some issues need further consideration. Issues such as unjustified interpretations, lack of attention to the pharmacokinetics profile and weak study design may affect the final decision about the use of plants as anticancer agents and possibly needs reconsideration. In this review, we have summarized the potential health benefits of Scutellaria and its active components also the underlying mechanism of cytotoxicity and antitumor activity. Meanwhile we have discussed concerns may interfere with the precise conclusion.

Alterations in antioxidant function and cell apoptosis in duck spleen exposed to molybdenum and/or cadmium

To investigate the effects of molybdenum (Mo) and/or cadmium (Cd) on antioxidant function and the apoptosis-related genes in duck spleens. Sixty healthy 11-day-old ducks were randomly divided into six groups of 10 ducks (control, low Mo group, high Mo, Cd, low Mo + Cd, and high Mo + Cd groups). All were fed a basal diet containing low or high dietary doses of Mo and/or Cd. Relative spleen weight, antioxidant indices, apoptosis-related gene mRNA expression levels, and ultrastructural changes were evaluated after 120 days. The results showed that the relative spleen weight decreased significantly in the high Mo + Cd treatment group which compared with control group. Malondialdehyde levels increased and xanthine oxidase and catalase activities decreased in the Mo and/or Cd groups compared with levels in the control group. Bak-1 and Caspase-3 expressions were upregulated in the high Mo + Cd group, while Bcl-2 was downregulated. In addition, mitochondrial crest fracture, swelling, vacuolation, deformed nuclei, and karyopyknosis in both Mo + Cd treated groups were more severe than in the other groups. The results suggest that Mo and/or Cd can induce oxidative stress and apoptosis of spleen via effects on the mitochondrial intrinsic pathway. Moreover, the results indicate the two elements have a possible synergistic relationship.

In vitro protective effects of Scutellaria litwinowii root extract against H2O2-induced DNA damage and cytotoxicity

BACKGROUND

Despite the wide range of investigations on the therapeutic potentials of herbal extracts in cancer cell lines, there is not usually enough data on their probable effects on normal cells. Recently, both anti-tumoral and anti-oxidant properties of Scutellaria litwinowii extracts have been reported on different cancer cell lines. In the present study, the possible protective effects of S. litwinowii root extracts against cytotoxicity and DNA damage induced by hydrogen peroxide (H2O2) on normal cells were investigated using MTT and Comet assays, respectively.

METHODS

A method of sequential extraction with solvents of different polarities was used to generate methanolic, de-fatted, and dichloromethane fractions. Both MTT and Comet assays were performed here to assess, respectively, changes in cell viability and levels of DNA damage from H2O2. In a pre-treatment regimen, test materials were applied to the cells prior to H2O2 treatment, while in a co-treatment protocol, cells were treated simultaneously with H2O2 and extracts.

RESULTS

In the co-treatment studies, only methanolic extract at 1,000 μg/mL (p<0.001) imparted a significant protective effect as shown in the MTT assay. Pre-treatment of cells for 24 h with different concentrations of the test materials did not lead to any significant protection. Results from the Comet assays in the co-treatment studies suggested a significant (p<0.01) protective effect of the test materials against DNA damage caused by H2O2. However, in the pre-treatment studies, only methanolic extract at ≥500 μg/mL showed a protective effect (p<0.01).

CONCLUSIONS

Considering the probable high levels of phenolic and flavonoid compounds in the methanolic extract, these compounds may impart the noted protective effects of the S. litwinowii root through the scavenging of free radicals.

Growth inhibition and apoptosis induction by Scutellaria pinnatifida A. Ham. on HL-60 and K562 leukemic cell lines

A rich flavonoid plant extensively used in traditional medicine is Scutellaria (Lamiaceae). In this study the cytotoxic effects of different extracts of Scutellaria pinnatifida were explored on two different cancer cell lines including K562 and HL-60 and a normal cell line. Also, the role of apoptosis on this toxicity was explored. The cell viability was quantitated by alamarBlue(®) assay. S. pinnatifida could effectively decrease the viability of malignant cells and the CH2Cl2 extract of S. pinnatifida had showed the most cytotoxic effects among other extracts. Apoptosis was confirmed after propidium iodide staining of DNA fragments and detection of the sub-G1 peak in the related flow cytometry histogram of cells. The results of western blot assay showed that CH2Cl2 extract has been able to increase the amount of Bax and cleavage of PARP protein after a 48h contact with cells. Neobaicalein (skullcapflavone II) and wogonin were identified in the extract of S. pinnatifida as the active components. The result of the present study confirmed the putative role of neobaicalein (skullcapflavone II) and wogonin as cytotoxic components in the CH2Cl2 extract of S. pinnatifida.

Comparative studies of cytotoxic and apoptotic properties of different extracts and the essential oil of Lavandula angustifolia on malignant and normal cells

Lavender (Lavandula angustifolia Mill.) is a bush-like shrub from Lamiaceae. The herb has been used in alternative medicine for several centuries. In this study, the cytotoxicity and the mechanisms of cell death induced by 3 different extracts of aerial parts and the essential oil of L. angustifolia were compared in normal and cancerous human cells. Malignant (HeLa and MCF-7 cell lines) and nonmalignant (human fibroblasts) cells were incubated with different concentrations of the plant extracts. Cell viability was quantified by MTS assay. Apoptotic cells were determined using propidium iodide staining of DNA fragmentation by flow cytometry (sub-G1 peak). The molecules as apoptotic signal translation, including Bax and cleaved PARP, were identified by Western blot. Ethanol and n-hexane extracts and essential oil exhibited significant cytotoxicity to malignant cells but marginal cytotoxicity to human fibroblasts in vitro and induced a sub-G1 peak in flow cytometry histogram of treated cells compared to the control. Western blot analysis demonstrated that EtOH and n-hexane extracts upregulated Bax expression, also it induced cleavage of PARP in HeLa cells compared to the control. In conclusion, L. angustifolia has cytotoxic and apoptotic effects in HeLa and MCF-7 cell lines, and apoptosis is proposed as the possible mechanism of action.

Oxymatrine triggers apoptosis by regulating Bcl-2 family proteins and activating caspase-3/caspase-9 pathway in human leukemia HL-60 cells

With the objective of identifying promising antitumor agents for human leukemia, we carried out to determine the anticancer ability of oxymatrine on the human leukemia HL-60 cell line. In vitro experiments demonstrated that oxymatrine reduced the proliferation of HL-60 cells in a dose- and time-dependent manner via the induction of apoptosis and cell cycle arrest at G2/M and S phases. The proteins involved in oxymatrine-induced apoptosis in HL-60 cells were also examined using Western blot. The increase in apoptosis upon treatment with oxymatrine was correlated with downregulation of anti-apoptotic Bcl-2 expression and upregulation of pro-apoptotic Bax expression. Furthermore, oxymatrine induced the activation of caspase-3 and caspase-9 and the cleavage of poly(ADP-ribose) polymerase (PARP) in HL-60 cells. In addition, pretreatment with a specific caspase-3 (Z-DEVD-FMK) or caspase-9 (Z-LEHD-FMK) inhibitor significantly neutralized the pro-apoptotic activity of oxymatrine in HL-60 cells, demonstrating the important role of caspase-3 and caspase-9 in this process. Taken together, these results indicated that oxymatrine-induced apoptosis may occur through the activation of the caspase-9/caspase-3-mediated intrinsic pathway. Therefore, oxymatrine may be a potential candidate for the treatment of human leukemia.

Protective Effect of Scutellaria litwinowii Extract on Serum/Glucose-Deprived Cultured PC12 Cells and Determining the Role of Reactive Oxygen Species

Considering the wide, positive reporting of the role of reactive oxygen species in ischemic brain injury, searching for antioxidant drugs within herbal remedies is logical. In this study, the protective effects of Scutellaria litwinowii Bornm. & Sint. on cell viability and reactive oxygen species production in cultured PC12 cells were investigated under serum/glucose-deprivation-induced cell death. After cells were seeded overnight, they were then deprived of serum/glucose for 24 h. Cells were treated with different concentrations of S. litwinowii extract (7.75–250 μg/mL). Cell viability was quantitated by MTT assay, and intracellular reactive oxygen species production was measured by flow cytometry. Serum/glucose-deprivation induced significant cell death after 24 h (P < 0.001). Treatment with S. litwinowii (7.75–250 μg/mL) reduced serum/glucose deprivation-induced cytotoxicity in PC12 cells after 24 h. A significant increase in intracellular reactive oxygen species production was seen following serum/glucose deprivation (P < 0.001). S. litwinowii (62 and 125 μg/mL, P < 0.01) treatment reversed the increased reactive oxygen species production following ischemic insult. This demonstrates that S. litwinowii extract protects PC12 cells against serum/glucose-deprivation-induced cell death by antioxidant mechanisms, which indicates the potential therapeutic application of S. litwinowii in managing cerebral ischemic and neurodegenerative disorders.