Su-Tze Chou

Cinnamomum cassia Essential Oil Inhibits α-MSH-Induced Melanin Production and Oxidative Stress in Murine B16 Melanoma Cells

Essential oils extracted from aromatic plants exhibit important biological activities and have become increasingly important for the development of aromatherapy for complementary and alternative medicine. The essential oil extracted from Cinnamomum cassia Presl (CC-EO) has various functional properties; however, little information is available regarding its anti-tyrosinase and anti-melanogenic activities. In this study, 16 compounds in the CC-EO have been identified; the major components of this oil are cis-2-methoxycinnamic acid (43.06%) and cinnamaldehyde (42.37%). CC-EO and cinnamaldehyde exhibited anti-tyrosinase activities; however, cis-2-methoxycinnamic acid did not demonstrate tyrosinase inhibitory activity. In murine B16 melanoma cells stimulated with α-melanocyte-stimulating hormone (α-MSH), CC-EO and cinnamaldehyde not only reduced the melanin content and tyrosinase activity of the cells but also down-regulated tyrosinase expression without exhibiting cytotoxicity. Moreover, CC-EO and cinnamaldehyde decreased thiobarbituric acid-reactive substance (TBARS) levels and restored glutathione (GSH) and catalase activity in the α-MSH-stimulated B16 cells. These results demonstrate that CC-EO and its major component, cinnamaldehyde, possess potent anti-tyrosinase and anti-melanogenic activities that are coupled with antioxidant properties. Therefore, CC-EO may be a good source of skin-whitening agents and may have potential as an antioxidant in the future development of complementary and alternative medicine-based aromatherapy.

The Melanogenesis Alteration Effects of Achillea millefolium L. Essential Oil and Linalyl Acetate: Involvement of Oxidative Stress and the JNK and ERK Signaling Pathways in Melanoma Cells

The mitogen-activated protein kinase (MAPK) family, including extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK)1/2 and p38 MAPK, is known to be activated by ultraviolet (UV) radiation in melanocytes to regulate melanin production. Reactive oxygen species (ROS) play important roles in the pathway of ERK and JNK activation. It has been established that the essential oil of Achillea millefolium L. (AM-EO) has activities that suppress the oxidative stress and inflammatory responses. Thus, we analyzed the effects of AM-EO on melanogenesis in melanocyte stimulating hormone (α-MSH) treated melanoma cells. The results demonstrated that AM-EO suppresses melanin production by decreasing tyrosinase activity through the regulation of the JNK and ERK signaling pathways. This effect might be associated with the AM-EO activity leading to the suppression of ROS, and linalyl acetate is its major functional component. Therefore, we propose that AM-EO has the potential to treat hyperpigmentation in the future.

Achillea millefolium L. essential oil inhibits LPS-induced oxidative stress and nitric oxide production in RAW 264.7 Macrophages.

Achillea millefolium L. is a member of the Asteraceae family and has been used in folk medicine in many countries. In this study, 19 compounds in A. millefolium essential oil (AM-EO) have been identified; the major components are artemisia ketone (14.92%), camphor (11.64%), linalyl acetate (11.51%) and 1,8-cineole (10.15%). AM-EO can suppress the inflammatory responses of lipopolysaccharides (LPS)-stimulated RAW 264.7 macrophages, including decreased levels of cellular nitric oxide (NO) and superoxide anion production, lipid peroxidation and glutathione (GSH) concentration. This antioxidant activity is not a result of increased superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, but rather occurs as a result of the down-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and heme oxygenase-1 (HO-1) expression, thus reducing the inflammatory response. Therefore, AM-EO can be utilized in many applications, including the treatment of inflammatory diseases in the future.

Chemical composition and tyrosinase inhibitory activity of Cinnamomum cassia essential oil

BackgroundEssential oils extracted from aromatic plants exhibit important biological activities and have become increasingly important for scientific research. The essential oil extracted from Cinnamomum cassia Presl (CC-EO) has various functional properties, however, little information is available regarding the tyrosinase inhibitory activity. Therefore, the objectives of this study were to investigate the chemical composition and tyrosinase inhibitory activity of the CC-EO.Resultscis-2-methoxycinnamic acid (43.06%) and cinnamaldehyde (42.37%) were found to be the two major components of the CC-EO identified by gas chromatography–mass spectrometry (GC-MS). The inhibitory activities of CC-EO and its major constituents were further evaluated against mushroom tyrosinase. The results showed that CC-EO and cinnamaldehyde exhibited anti-tyrosinase activities with IC50 values of 6.16 ± 0.04 mg/mL and 4.04 ± 0.08 mg/mL, respectively. However, cis-2-methoxycinnamic acid did not show any anti-tyrosinase activity. The inhibition kinetics were analyzed by Lineweaver-Burk plots and second replots, which revealed that CC-EO and cinnamaldehyde were mixed-type inhibitors. The inhibition constants (Ki) for CC-EO and cinnamaldehyde were calculated to be 4.71 ± 0.09 mg/mL and 2.38 ± 0.09 mg/mL, respectively.ConclusionThese results demonstrate that CC-EO and its major component, cinnamaldehyde, possess potent anti-tyrosinase activities and may be a good source for skin-whitening agents.

Graptopetalum paraguayense E. Walther Leaf Extracts Protect Against Brain Injury in Ischemic Rats

As practice in folk medicine, Graptopetalum paraguayense E. Walther possesses several biological/pharmacological activities including hepatoprotective, anti-oxidant, and anti-inflammatory. We investigated the neuroprotective potential of Graptopetalum paraguayense E. Walther leaf extracts on inflammation-mediated ischemic brain injury. Water (GWE), 50% alcohol (GE50) extracts of Graptopetalum paraguayense E. Walther, and extracts obtained from further extraction of GE50 with ethyl acetate (GEE) were used. Oral administration of GEE, but not GWE or GE50, for 2 weeks protected animals against cerebral ischemia/reperfusion brain injury. The neuroprotective effect of GEE was accompanied by reductions in brain infarction, neurological deficits, caspase-3 activity, malondialdehyde content, microglia activation, and inducible nitric oxide synthase (iNOS) expression. Since microglia-mediated inflammation plays critical roles in ischemic brain injury, anti-inflammatory potential of Graptopetalum paraguayense E. Walther leaf extracts was further investigated on lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma-activated BV-2 microglial cells. GEE decreased H(2)O(2)- and LPS/IFN-gamma-induced free radical generation and LPS/IFN-gamma-induced iNOS expression. Mechanistic study revealed that the neuroactive effects of GEE were markedly associated with anti-oxidative potential, activation of serine/threonine and tyrosine phosphatases, and down-regulation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, Akt, Src, Janus kinase-1, Tyk2, signal transducer and activator of transcription-1, and NF-kappaB and might be attributed to the presence of polyphenolic compounds such as gallic acid, genistin, daidzin, and quercetin. Together, our findings point out its potential therapeutic strategies that target microglia activation, oxidative stress, and iNOS expression to reduce ischemic brain injury and suggest that Graptopetalum paraguayense E. Walther leaf extracts represent a valuable source for the development of neuroprotective agents.

Effect of Vetiveria zizanioides essential oil on melanogenesis in melanoma cells: downregulation of tyrosinase expression and suppression of oxidative stress.

The major objective of this study was to estimate the hypopigmentation function of the essential oil from Vetiveria zizanioides (VZ-EO). Our results indicated that VZ-EO exhibits potent lipid peroxidation inhibitory activity to moderate the bleaching of β-carotene and to maintain the cellular glutathione (GSH) levels. VZ-EO can markedly decrease melanin production and tyrosinase activity in α-melanin-stimulating-hormone- (α-MSH-) stimulated B16 cells. The effect of VZ-EO on melanogenesis is achieved by the suppression of cellular tyrosinase expression. The results demonstrated that the activity of VZ-EO on melanogenesis might be the result of its potent antioxidative ability, which was reflected in the decreased cellular oxidant and malondialdehyde (MDA) levels and the recovered activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) in α-MSH-stimulated B16 cells. The most abundant compound in VZ-EO is cedr-8-en-13-ol (12.4%), which has a strong capability to inhibit lipid peroxidation. Therefore, VZ-EO has the potential to become an ingredient in future hypopigmentation drugs, foods, and cosmetics.

The effects of Caulerpa microphysa enzyme-digested extracts on ACE-inhibitory activity and in vitro anti-tumour properties.

The aim of this study was to determine the ACE inhibitory activity and its anti-cancer properties of Caulerpa microphysa extracts. C. microphysa samples were digested with Flavourzyme, Alcalase, and pepsin. The ACE inhibitory activity of enzyme-digested C. microphysa decreased in the order of digestion with pepsin>Flavourzyme>Alcalase; that is, pepsin-extracted samples had significantly higher activity than the other enzyme extractions. To test its anti-tumour effects in vitro C. microphysa pepsin-digested extracts were applied to BALB/c mice with transplanted myelomonocytic leukaemia (WEHI-3) and Human promyelocytic leukaemia (HL-60) cell lines. The growth of both cell lines was inhibited, and extracts induced DNA damage, evaluated with a comet assay. The data demonstrate that C. microphysa pepsin-digested extract had the ability to anti-tumour effects. Further application as a health food is worthy of investigation.

Cinnamomum cassia essential oil and its major constituent cinnamaldehyde induced cell cycle arrest and apoptosis in human oral squamous cell carcinoma HSC-3 cells

Cinnamomum cassia essential oil (CC‐EO) has various functional properties, such as anti‐microbial, hypouricemic, anti‐tyrosinase and anti‐melanogenesis activities. The present study aimed to evaluate the anti‐cancer activities of CC‐EO and its major constituent, cinnamaldehyde, in human oral squamous cell carcinoma HSC‐3 cells. Determination of the cell viability, apoptotic characteristics, DNA damage, cell cycle analysis, reactive oxygen species (ROS) production, mitochondrial membrane potential, cytosolic Ca2+ level and intracellular redox status were performed. Our results demonstrated that CC‐EO and cinnamaldehyde significantly decreased cell viability and caused morphological changes. The cell cycle analysis revealed that CC‐EO and cinnamaldehyde induced G2/M cell cycle arrest in HSC‐3 cells. The apoptotic characteristics (DNA laddering and chromatin condensation) and DNA damage were observed in the CC‐EO‐treated and cinnamaldehyde‐treated HSC‐3 cells. Moreover, CC‐EO and cinnamaldehyde promoted an increase in cytosolic Ca2+ levels, induced mitochondrial dysfunction and activated cytochrome c release. The results of ROS production and intracellular redox status demonstrated that CC‐EO and cinnamaldehyde significantly increased the ROS production and thiobarbituric acid reactive substance levels, and the cellular glutathione content and glutathione peroxidase activity were significantly reduced in HSC‐3 cells. Our results suggest that CC‐EO and cinnamaldehyde may possess anti‐oral cancer activity in HSC‐3 cells.

Melaleuca quinquenervia essential oil inhibits α-melanocyte-stimulating hormone-induced melanin production and oxidative stress in B16 melanoma cells

BACKGROUND Essential oils are odorous, volatile products of plant secondary metabolism, which are found in many leaves and stems. They show important biological activities, which account for the development of aromatherapy used in complementary and alternative medicine. The essential oil extracted from Melaleuca quinquenervia (Cav.) S.T. Blake (paperbark) (MQ-EO) has various functional properties. PURPOSE The aim of this study is to investigate the chemical composition of MQ-EO by using gas chromatography-mass spectrometry (GC-MS) and evaluate its tyrosinase inhibitory activity. METHODS Gas chromatography-mass spectrometry (GC-MS)-based metabolomics was used to identify 18 components in MQ-EO. The main components identified were 1,8-cineole (21.60%), α-pinene (15.93%), viridiflorol (14.55%), and α-terpineol (13.73%). B16 melanoma cells were treated with α-melanocyte-stimulating hormone (α-MSH) in the presence of various concentrations of MQ-EO or its major compounds. Cell viability was accessed by MTT assay and cellular tyrosinase activity and melanin content were determined by using spectrophotographic methods. The antioxidant mechanism of MQ-EO in α-MSH stimulated B16 cells was also investigated. RESULTS In α-melanocyte-stimulating hormone (α-MSH)-stimulated murine B16 melanoma cells, MQ-EO, 1,8-cineole, α-pinene, and α-terpineol significantly reduced melanin content and tyrosinase activity. Moreover, MQ-EO, 1,8-cineole, α-pinene, and α-terpineol decreased malondialdehyde (MDA) levels. In addition, restored glutathione (GSH) levels, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase activities were increased in α-MSH-stimulated B16 cells. MQ-EO not only decreased apoptosis but also reduced DNA damage in α-MSH stimulated B16 cells. These results showed that MQ-EO and its main components, 1,8-cineole, α-pinene, and α-terpineol, possessed potent anti-tyrosinase and anti-melanogenic activities besides the antioxidant properties. CONCLUSIONS The active functional components of MQ-EO were found to be 1,8-cineole, α-pinene, and α-terpineol. Consequently, the results of present study suggest that MQ-EO is non-cytotoxic and can be used as a skin-whitening agent, both medically and cosmetically.

Improving antioxidant status in aged mice by 50% ethanol extract from red bean fermented by Bacillus subtilis.

BACKGROUND The purpose of this study was to investigate the effects of 50% ethanol extracts from red bean non-fermented (RBE) and fermented by Bacillus subtilis (RBNE) on the antioxidant status of aged ICR mouse. RESULTS Compared to 2-month-old ICR mouse, the plasma total antioxidant status (TAS) in 12-month-old ICR mouse decreased about 57%, while malondialdehyde (MDA) levels in the liver and brain of 12-month-old ICR mouse increased 56% and 30%, respectively. Orally administration of RBE or RBNE could completely recover the changes of MDA and plasma TAS levels due to the aging process. Vitamin E contents declined 88% in the liver and 74% in the brain of aged ICR mouse. At a level of 0.3 or 0.6 g kg(-1) body weight, RBNE raised vitamin E content in the liver and brain; however, RBE showed no significant influence. All antioxidant enzymes activities in the liver and brain of aged ICR mouse decreased compared to those activities in 2-month-old ICR mouse. RBNE could significantly enhance the superoxide dismutase activity in the brain of aged ICR mouse. CONCLUSION Oral administration of RBE or RBNE could improve antioxidant status in aged ICR mouse. Fermentation by Bacillus subtilis could enhance the antioxidant properties of red bean.