Neuroprotective Effects of Sesamum indicum, Sesamin and Sesamolin Against 6-OHDA-induced Apoptosis in PC12 Cells.

BACKGROUND: Sesamum indicum L. (sesame) is one of the most widely used herbs in the world. Sesame oil contains lignans such as sesamin and sesamolin, which are known to possess anti-inflammatory, antioxidant, and anti-apoptotic properties. Parkinson's disease (PD) is recognized as the most common neurodegenerative disease after Alzheimer's disease; however, the exact molecular mechanism of the progression of neural death is not clear yet. In this study, the effect of sesame seed extracts and their main bioactive components (sesamin and sesamolin) on in vitro model of Parkinson's disease has been compared. METHODS: Cell viability, the number of reactive oxygen species (ROS), and apoptosis were determined using resazurin assay, ROS assay, propidium iodide (PI) staining and flow cytometry, and western blot analysis. RESULTS: 6-OHDA caused cellular death and apoptosis but pretreatment with sesame seed extracts, sesamin, and sesamolin significantly increased cell viability (p<0.001) and decreased ROS (p<0.001) and apoptosis. ERK1/2 is activated by 6-OHDA in PC12 cells, and the level of survivin decreased. Pretreatment with sesame significantly reversed the entire cell death induced by 6- OHDA. Sesame seed extracts at 5 and 10 µg/ml, sesamin and sesamolin at 5 and 10 µM increased surviving (p<0.01), and reduced P-ERK1/2/ERK1/2 (p<0.05) levels close to the control values. CONCLUSIONS: Overall, compounds in sesame seed extract and sesamin may assist as adjuvant therapeutics in PD. It seems sesame seeds have more potent protection effects against neural death compared with individual components, which might reflect the synergism among different phytochemicals present in the extract.

Neobaicalein, a flavonoid from the Scutellaria litwinowii Bornm. & Sint. ex Bornm. induced apoptosis in human leukemic cell lines.

Objectives: Neobaicalein is one of the rich plant flavonoids isolated from the roots of Scutellaria spp. In this study, we evaluated and compared cytotoxic activity and the related apoptosis mechanisms of neobaicalein from Scutellaria litwinowii Bornm. & Sint. ex Bornm on apoptosis-proficient HL-60 cells and apoptosis-resistant K562 cells. Materials and Methods: Cell viability, cell apoptosis, caspase activity, and apoptosis-related protein expression were measured using MTS assay, propidium iodide (PI) staining and flow cytometry, caspase activity assay, and western blot analysis, respectively. Results: Neobaicalein significantly reduced cell viability in a dose-dependent manner using the MTS assay (P<0.05). The IC50 values (µM) against HL-60 and K562 cells after 48 hr treatment were 40.5 and 84.8, respectively. Incubation of HL-60 and K562 cells with 25, 50, and 100 µM neobaicalein for 48 hr, significantly increased the number of apoptotic cells and showed cytotoxic effects compared with the control group. Treatment with neobaicalein significantly increased Fas (P<0.05) and the cleaved form of PARP (P<0.05), and decreased the Bcl-2 levels (P<0.05) in HL-60 cells, whereas neobaicalein significantly increased Bax (P<0.05) and the cleaved form of PARP (P<0.05), and the caspases of the extrinsic and intrinsic pathways including caspases-8 (P<0.0001), -9 (P<0.01), and effector caspase-3 (P<0.0001) levels in K562 cells compared with the control group. Conclusion: It seems neobaicalein might cause cytotoxicity and cell apoptosis through interaction with the different apoptosis-related proteins of apoptotic pathways in HL-60 and K562 cells. Neobaicalein may exert a beneficial protective effect in slowing the progression of hematological malignancies.

Pharmacological and biological effects of alpha-bisabolol: An updated review of the molecular mechanisms.

Alpha-bisabolol (α-bisabolol), an unsaturated monocyclic sesquiterpene alcohol, is known as one of the "most-used herbal constituents" in the world. Various therapeutic and biological properties of α-bisabolol in preventing oxidative stress, inflammatory disorders, infections, neurodegenerative diseases, cancers, and metabolic disorders have been reported. In this review, we evaluated new findings regarding the molecular mechanisms of α-bisabolol published from 2010 until 2021 in PubMed, Science Direct, and Scopus. The antioxidant mechanism of α-bisabolol is mainly associated with the reduction of ROS/RNS, MDA, and GSH depletion, MPO activity, and augmentation of SOD and CAT. Additionally, upregulating the expression of bcl-2 and suppression of bax, P53, APAF-1, caspase-3, and caspase-9 activity indicates the anti-apoptotic effects of α- bisabolol. It possesses anti-inflammatory effects via reduction of TNF-α, IL-1ß, IL-6, iNOS, and COX-2 and suppresses the activation of ERK1/2, JNK, NF-κB, and p38. The antimicrobial effect is mediated by inhibiting the viability of infected cells and improves cognitive function via downregulation of bax, cleaved caspases-3 and 9 levels, ß-secretase, cholinesterase activities, and upregulation of bcl-2 levels. Finally, due to multiple biological activities, α-bisabolol is worthy to be subjected to clinical trials to achieve new insights into its beneficial effects on human health.

Protective effects of 6-gingerol on 6-hydroxydopamine-induced apoptosis in PC12 cells through modulation of SAPK/JNK and survivin activation.

Due to many therapeutic effects, Ginger (Zingiber officinale) is the most widely used spice around the world, including in Iran. Due to its potent anti-inflammatory and antioxidant effects, ginger may protect against neurodegenerative disorders. Here, we investigated the effects of 6-gingerol (the main bioactive compound in ginger) on 6-hydroxydopamine (6-OHDA)-induced cell death in PC12 cells. Cell viability, cell apoptosis, and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), and survivin expression were measured using resazurin, propidium iodide (PI) and flow cytometry, and western blot analysis. 6-OHDA (100 µM) reduced the cell viability, increased apoptosis, increased the active form of SAPK/JNK, and decreased survivin protein level in PC12 exposed cells in a dose and time-dependent manner. Pretreatment with 6-gingerol significantly increased the viability and reduced apoptosis (2.5 and 5 µM). Also, pretreatment with 6-gingerol at 2.5 and 5 µM increased survivin whereas, 6-gingerol at 2.5 µM reduced (P-SAPK/JNK):(SAPK/JNK) levels to a level near that of the related control. According to the results, 6-gingerol blocks 6-OHDA-induced cell damage by suppressing oxidative stress and anti-apoptotic activity. Thus, 6-gingerol may process beneficial protective effects in slowing the progression of Parkinson's disease.

Biological and Pharmacological Effects of Gamma-oryzanol: An Updated Review of the Molecular Mechanisms.

BACKGROUND: Gamma-oryzanol (γ-oryzanol) is one of the rice bran oil (RBO) compounds, known as a principal food source throughout the world. In recent numerous experimental studies, γ-oryzanol has been revealed to have several useful pharmacological properties, such as anti-oxidant, anti-inflammatory, anti-cancer, anti-diabetic, ameliorating unpleasant menopausal symptoms, cholesterol-lowering, improving plasma lipid pattern, etc. Methods: In this study, we reviewed the scientific literature published up until 2020, which has evaluated the biological and pharmacological activity of gamma-oryzanol. This review summarizes the published data found in PubMed, Science Direct, and Scopus. RESULTS AND CONCLUSION: The present review attempts to summarize the most related articles about the pharmacological and therapeutic potential from recent studies on γ-oryzanol to gain insights into design further studies to achieve new evidence that confirm the observed effects.

Comparison of the cytotoxic effects of different fractions of Artemisia ciniformis and Artemisia biennis on B16/F10, PC3 and MCF7 Cells.

BACKGROUND AND PURPOSE: Artemisia is one of the well-known herbal medicinal plants for antimicrobial, insecticidal, antioxidant, and antimalarial activities. The antiproliferative effects of dichloromethane extracts of Artemisia biennis (A. biennis) and A. ciniformis and the petroleum ether extract of A. ciniformis have been demonstrated previously on human cancerous cell lines. In the current study, further fractionation was carried out on the aforementioned extracts and their cytotoxic effects were evaluated on three human cancer cell lines; B16/F10, PC3, and MCF7. F1 to F16, F1' to F11', and F1" to F10" were resulted from the fractionation of dichloromethane extracts of A. biennis, A. ciniformis, and petroleum ether extract of A. ciniformis, respectively. EXPERIMENTAL APPROACH: The cytotoxic effects of 16 (F1-F16), 11 (F1'-F11') and 10 (F1"-F10") fractions, on B16/F10, PC3, and MCF7 cell lines were assessed using resazurin to measure viability and propidium iodide staining (sub G1) and flow cytometry to detect apoptosis. FINDINGS / RESULTS: The results showed that, some fractions at 100 µg/mL decreased cell viability. F2" in B16/F10 cells, F2, F4-F6, F10', F11', and F2" in PC3 cells, and F10', F11', and F2" in MCF7 significantly decreased cell viability in a concentration-dependent manner (12.5-50 µg/mL). Among different fractions, F2" demonstrated the most potent cytotoxic effects on cancer cell lines (P < 0.001). All of the mentioned fractions (except F11' on PC3 cells) increased the number of apoptotic cells and showed the cytotoxic effects on cancer cells compared with the control group. CONCLUSION AND IMPLICATIONS: A. biennis and A. ciniformis are suggested as the potential sources of cytotoxic phytochemicals. The probable presence of terpenoids, steroids, and alkaloids in the selected fractions is proposed based on the preliminary phytochemical study.

Protective effects of Cinnamomum verum, Cinnamomum cassia and cinnamaldehyde against 6-OHDA-induced apoptosis in PC12 cells.

Cinnamon (Cinnamomum verum and C. cassia) is a medicinal plant, widely-used as a culinary spice. It possesses various therapeutic effects and can slow down the progression of neurological disorders impressively. In this article, the effects of hydro-alcohol extract and essential oil of C. verum and C. cassia and its main bioactive component cinnamaldehyde, has been examined on 6-OHDA-exposed PC12 cells as an in vitro model of Parkinson's disease. The cytotoxicity and cell apoptosis has been induced by 6-OHDA in PC12 cells. The protective effect was determined by measuring cell viability, the amount of reactive oxygen species (ROS), and apoptosis. Cell viability and apoptosis were assessed using resazurin assay, flow cytometry of propidium iodide (PI) stained cells, and western blot analysis. 6-OHDA resulted in the death and apoptosis of cells while, pretreatment with the extract and essential oil of C. verum and C. cassia at 20 µg/ml and cinnamaldehyde at 5 and 10 µM for 24 h could significantly increase the viability (p < 0.001), and decrease ROS content (p < 0.05). Pretreatment with the extracts increased survivin and decreased cyt-c whereas, pretreatment with the essential oil decreased cyt-c, increased survivin, and reduced P-p44/42/p44/42 levels to a level near that of the related control. The extract and essential oil of C. verum and C. cassia can be effective against 6-OHDA cytotoxicity. It is suggested that, the synergistic effects of cinnamaldehyde and other components of extract and essential oil promote cinnamon's medicinal properties.

Protective effects of vitamin K2 on 6-OHDA-induced apoptosis in PC12 cells through modulation bax and caspase-3 activation.

Neuroprotection using compounds with dual functions of anti-apoptotic and antioxidant effects fight against neurodegeneration. Vitamin K2 acts as a cofactor in many biochemical pathways, including sphingolipid synthesis in the nervous system, which is involved in many cellular events, including proliferation, differentiation, cellular communication, and alteration. This study aimed to investigate the protective effects of vitamin K2 in PC12 cells as an in vitro model of Parkinson's disease. The protective effects of vitamin K2 against 6-OHDA-induced apoptosis in PC12 cells were assessed using resazurin for viability, DCF-DA for ROS level, DTNB for glutathione level, flow cytometry for sub G1, and western blot analysis for detecting bax and pro-caspase-3 expression level. The results showed that 6-OHDA significantly decreased cell viability, glutathione and pro-caspase-3 levels, and increased ROS, the amount of bax in PC12 cells, while the pretreatment with 5 µM vitamin K2 significantly decreased the cell death induced by 6-OHDA. Generally, the results may present a new insight about the potential protective action of vitamin K2 against the progression of Parkinson's disease. Further studies may warrant the use of vitamin K2 as an antioxidant and anti-apoptotic agent in slowing nerve injury in neurodegenerative disease, particularly in Parkinson's disease.

Cytotoxic Activity of Thirteen Endemic and Rare Plants from Chaharmahal and Bakhtiari Province in Iran.

Chaharmahal and Bakhtiari Province is one of the most important endemism states of the flora of Iran with a considerable plant species diversity. In the present study, the cytotoxic activity of 13 plant species grown in Chaharmahal and Bakhtiari have been evaluated on prostate (PC-3), breast (MCF-7), liver (HepG2), ovary (CHO), and melanoma (B16-F10) cancer cell lines. The cytotoxicity and apoptotic activity of methanol extracts was evaluated using resazurin reagent and flow cytometry of PI stained cells, respectively. Methanol extracts of Dionysia sawyeri, Stachys obtusicrena and Cicer oxyodon on CHO cell line (p <0.05) and D. sawyer and Linum album on B16/F10 cell line (p <0.05) showed significant cytotoxic effects and increased apoptosis. It is generally suggested that the plant extracts with low IC50 values are likely to be used as anti-cancer compounds in reducing cancer progression in scientific studies.

The Role of SAPK/JNK Pathway in the Synergistic Effects of Metformin and Dacarbazine on Apoptosis in Raji and Ramos Lymphoma Cells.

BACKGROUND: Besides the first-line medication for the treatment of type 2 diabetes, the growth inhibitory activity of metformin alone or in combination with conventional chemotherapeutics has been addressed on a panel of cell lines. In this study, we investigated the cytotoxicity and apoptosis of the metformin alone and in combination with dacarbazine in Raji and Ramos lymphoma cell lines. METHODS: Cell viability and apoptosis measured using resazurin assay, flow cytometry of PI stained cells and western blot analysis. RESULTS: Metformin showed synergistic cytotoxic effects in combination with dacarbazine, reduced cell viability, and increased apoptosis in Raji and Ramos lymphoma cells in comparison with the use of each drug alone. The activation of MAPK and SAPK/JNK (P-SAPK/JNK) were shown in both cells. CONCLUSION: Overall, the result verified the synergistic effect of the metformin-dacarbazine combination, which has the value in reducing the chemotherapeutic agent dose, adverse effect and the burden of treatment for the community and patients.