Citri Reticulatae Pericarpium Limits TLR-4-Triggered Inflammatory Response in Raw264.7 Macrophages by Activating RasGRP3.

Inflammation is an important immune response to pathogen invasion, but excessive inflammation leads to tissue injury and even cytokine storm. Therefore, proper response is needed depending on the intensity of the infection. Ras guanine nucleotide releasing protein 3 (RasGRP3) is a regulator of the TLR-mediated response. In low-intensity inflammation, it negatively regulates production of pro-inflammatory cytokines, especially IL-6. Citri Reticulatae Pericarpium, the peel of Citrus reticulata Blanco, is a major medicinal herb in Korean medicine. The present study aims to investigate whether the Citri Reticulatae Pericarpium extract (CRE) has immunomodulatory activity using the Raw264.7 macrophage. Also, we investigated the effect of CRE on RasGRP3 expression. In the present study, CRE reduced IL-6 production in the low-LPS environment (1 ng/mL) and did not in the high-LPS environment (100 ng/mL). The suppression of IL-6 production in the low-LPS environment (1 ng/mL) was abolished after the pretreatment of RasGRP3 siRNA. The reduced RasGRP3 protein content by 100 ng/mL LPS treatment was increased by CRE treatment. Additionally, nobiletin, a major component of CRE showed a suppressive effect on IL-6 production in the low-LPS environment (1 ng/mL). The present results suggest that CRE alleviates inflammatory response via activating RasGRP3 expression in low-intensity inflammation.

Standardized extract of Glehnia Littoralis abrogates memory impairment and neuroinflammation by regulation of CREB/BDNF and NF-κB/MAPK signaling in scopolamine-induced amnesic mice model.

Mild cognitive impairment is a typical symptom of early Alzheimer's disease (AD). Glehnia littoralis (G. littoralis), a medicinal halophyte plant commonly used to treat strokes, has been shown to possess some therapeutic qualities. In this study, we investigated the neuroprotective and anti-neuroinflammatory effects of a 50% ethanol extract of G. littoralis (GLE) on lipopolysccharide (LPS)-stimulated BV-2 cells and scopolamine-induced amnesic mice. In the in vitro study, GLE treatment (100, 200, and 400 µg/mL) markedly attenuated the translocation of NF-κB to the nucleus concomitantly with the significant mitigation of the LPS-induced production of inflammatory mediators, including NO, iNOS, COX-2, IL-6, and TNF-α. In addition, the GLE treatment suppressed the phosphorylation of MAPK signaling in the LPS-stimulated BV-2 cells. In the in vivo study, mice were orally administered with the GLE (50, 100, and 200 mg/kg) for 14 days, and cognitive loss was induced via the intraperitoneal injection of scopolamine (1 mg/kg) from 8 to 14 days. We found that GLE treatment ameliorated memory impairment and simultaneously improved memory function in the scopolamine-induced amnesic mice. Correspondingly, GLE treatment significantly decreased the AChE level and upregulated the protein expression of neuroprotective markers, such as BDNF and CREB, as well as Nrf2/HO-1 and decreased the levels of iNOS and COX-2 in the hippocampus and cortex. Furthermore, GLE treatment attenuated the increased phosphorylation of NF-κB/MAPK signaling in the hippocampus and cortex. These results suggest that GLE has a potential neuroprotective activity that may ameliorate learning and memory impairment by regulating AChE activity, promoting CREB/BDNF signaling, and inhibiting NF-κB/MAPK signaling and neuroinflammation.

Ethyl Acetate Fraction from a Catalpa ovata G. Don Extract Inhibits ɑ-MSH-Induced Melanogenesis through the cAMP/CREB Pathway.

The whitening effect of reducing skin pigmentation is one of the most important goals of cosmetics. The purpose of this study was to determine whether Catalpa ovata extract and its fractions have potential as natural skin-lightening agents. Initially, we screened various fractions of Catalpa ovata extract using an in vitro antioxidant assay. Then, the inhibitory effects of C. ovata extract and its fraction on melanogenesis and the related mechanisms were investigated in B16F1 melanoma cells. The results showed that the ethyl acetate fraction (EF) from C. ovata extract markedly inhibited melanin synthesis in a dose-dependent manner at non-toxic concentrations. Furthermore, EF downregulated both the protein and mRNA levels of tyrosinase, which is a specific enzyme that catalyzes the conversion of tyrosine into melanin. We also found that EF decreased the microphthalmia-associated transcription factor (MITF) at the protein and mRNA levels. EF increased the phosphorylation of ERK and suppressed the phosphorylation of JNK and p38 in ɑ-MSH-induced B16F1 cells. These results indicate that EF can regulate the MAPK pathway. In addition, EF has an anti-melanogenic effect via the downregulation of intracellular cyclic-AMP (cAMP). Nineteen major compounds of EF were identified using LC-MS/MS. Taken together, these results suggest that EF may be a potential anti-melanogenic agent for use in skin-whitening cosmetics and in topical treatments for hyperpigmentation disorders.

Dioscorea nipponica Makino Rhizome Extract and Its Active Compound Dioscin Protect against Neuroinflammation and Scopolamine-Induced Memory Deficits.

Activation of microglial cells by intrinsic or extrinsic insult causes neuroinflammation, a common phenomenon in neurodegenerative diseases. Prevention of neuroinflammation may ameliorate many neurodegenerative disease progressions. Dioscorea nipponica Makino (DN) extract can alleviate muscular atrophy and inflammatory diseases; however, the efficacy and mechanism of action in microglial cells remain unknown. The current study investigates the possible anti-inflammatory effects and mechanisms of Dioscorea nipponica Makino ethanol extract and its steroidal saponin dioscin. Our in vitro study shows that Dioscorea nipponica rhizome ethanol extract (DNRE) and dioscin protect against lipopolysaccharide (LPS)-activated inflammatory responses in BV-2 microglial cells by inhibiting phosphorylation and the nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), resulting in the downregulation of pro-inflammatory cytokines and enzymes. Consistent with our previous report of dioscin-mediated enhancement of neurotrophic factors in dopaminergic cells, here we found that dioscin upregulates brain-derived neurotrophic factor (BDNF) and cAMP-response element binding protein (CREB) phosphorylation (pCREB) in the cerebral cortex and hippocampus regions of the mouse brain. Scopolamine treatment increased pro-inflammatory enzyme levels and reduced the expression of BDNF and pCREB in the hippocampus and cortex regions, which led to impaired learning and referencing memory in mice. Pre-treatment of dioscin for 7 days substantially enhanced mice performances in maze studies, indicating amelioration in cognitive deficits. In conclusion, DNRE and its active compound dioscin protect against neurotoxicity most likely by suppressing NF-κB phosphorylation and upregulating neurotrophic factor BDNF.

Immunostimulatory Activity of Polysaccharides Extracted from Celosia cristata Flowers.

Macrophages play a major role in innate immune responses by producing a variety of immune mediators and cytokines. The stimulation of macrophages by natural products may lead to an enhanced innate immune system. This study evaluated the immunostimulatory effects of a polysaccharide-rich crude fraction of Celosia cristata L. flowers (CCP) on murine macrophages. CCP treatment induced the production of inducible nitric oxide synthase, cyclooxygenase-2, and cytokines by macrophages. Mechanistically, the activation of mitogen-activated protein kinases, NF-κB and toll-like receptor 4 were found to be associated with the stimulatory functions of CCP. CCP was found to be primarily composed of galacturonic acid and glucose in addition to small amounts of arabinose and galactose. This study demonstrated that CCP may enhance the innate immune responses and potentially improve the immune functions in the body.

Antioxidant Activities of Viviparus Contectus Extract Against Tert-Butylhydroperoxide-Induced Oxidative Stress.

In this study, the antioxidant properties of Viviparus contectus (V. contectus) extract were evaluated for various radical scavenging activities, ferric reducing antioxidant power (FRAP), ABTS radical scavenging activity and oxygen radical absorbance capacity (ORAC). In addition, inhibition effect of the V. contectus extract against DNA scission induced by hydroxyl radical was measured. We also studied the protective effect of V. contectus extract against oxidative damage through measurements of intracellular reactive oxygen species (ROS) in Chang cells and zebrafish embryo. We found that V. contectus extract contains strong radical scavenging activities and antioxidant properties, which prevent tert-butylhydroperoxide (t-BHP)-induced oxidative stress, enhance cell viability, reduce ROS production, inhibit oxidative damage and improve mitochondrial function in Chang cells. Also, we determined that the V. contectus extract reduced ROS production mediated by t-BHP induced oxidative stress on zebrafish embryo.

Antioxidant and Protective Effects of Atrina Pectinata Extract.

Atrina pectinata (A. pectinata), called pen shell, is an edible shellfish that adheres to the seabed pointed downward and has a triangular shell reaching about 40 cm in length.In this study, we examined the antioxidant effect of an A. pectinata extract exhibiting various radical scavenging activities. These scavenging activities were evaluated using electron spin resonance. Anti-oxidant activities were also determined using the ferric reducing antioxidant power (FRAP) and the ABTS radical scavenging assays. Lipid peroxidation inhibitory activity was confirmed using ferric thiocyanate and thiobarbituric acid assays. Furthermore, the protective effect of the A. pectinata extract against t-BHP-induced oxidative stress on Chang cells were evaluated using MTT assay and the measurement of reactive oxygen species (ROS). These results showed that the A. pectinata extract have strong radical scavenging activities, and exerts protective effect against oxidative stress through reducing intracellular ROS content of Chang cells.

Anti-inflammatory Effects of Batillaria multiformis Water Extracts via NF-кB and MAPK Signaling Pathways in LPS-Induced RAW 264.7 Cells.

Batillaria multiformis (B. multiformis) belong to gastropods. They live generally in the sandpit of the lagoons and the estuaries of the intertidal zone. Most of them are distributed in Korea, Japan and China. In this study, we investigated the anti-inflammatory potential of B. multiformis water extracts (BMW). The results showed that the extracts significantly decreased the production of nitric oxide (NO) and pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in LPS-induced RAW 264.7 macrophages. In addition, the extracts suppressed the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in a dose dependent manner. Further investigation indicated that BMW suppressed phosphorylated c-Jun N-terminal kinase (JNK), extracellular regulated protein kinase (ERK) and p38 through the MAPK signaling pathway and influenced the NF-κB signaling pathway by suppressing the IκBα degradation in LPS-induced RAW 264.7 macrophages.

Scallop Extracts Inhibited LPS-Induced Inflammation by Suppressing MAPK and NF-κB Activation in RAW264.7 Macrophages.

Scallops belong to cosmopolitan family of bivalves which are found in any oceans. They are one of the most important marine fishery resources in the world. The shell, meat and pearl layer have a high utilization value and a lot of scallops are eaten as food. In this study, we established anti-inflammatory effect of Scallops water extract in lipopolysaccharide (LPS) stimulated RAW 264.7 mononuclear macrophage. Our results indicated that Scallop water extract effectively reduced the synthesis of nitric oxide (NO). In addition, Scallop water extract suppressed the reactive oxygen species (ROS) generation and the expression of IL-6 and TNF-α. Further investigation indicated that anti-inflammatory effect of Scallop water extract via suppressing downregulation of MAPK (JNK, p38 and ERK) and NF-κB signaling.

Lindera glauca (Siebold et Zucc.) Blume Stem Extracts Protect Against tert-Butyl Hydroperoxide-Induced Oxidative Stress.

In this study, we investigated the antioxidant and protective effect of Lindera glauca stem (LGS) extracts against oxidative stress. We compared antioxidant properties of water extract (LGSW) with ethanol extract (LGSE) by determining the contents responsible for antioxidant activities such as polyphenols and flavonoids. Antioxidant properties were also determined by 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and ferric reducing antioxidant power (FRAP). Lipid peroxidation was estimated using ferric thiocyanate (FTC) and thiobarbituric acid (TBA) method. Both LGSW and LGSE strongly inhibited lipid peroxidation. Especially, LGSE showed a protective effect through increasing cell viability, decreasing intracellular reactive oxygen species (ROS) against tert-butyl hydroperoxide-induced oxidative stress in Chang cells. Furthermore, LGSE increased antioxidant related enzyme activities such as catalase, glutathione S-transferase, glutathione peroxidase, and superoxide dismutase gene expression against oxidative stress in a zebrafish model. Our findings suggest that LGSE could be useful for developing potential therapeutic agents with protective effects against oxidative stress.

Neuroprotective Effect of Taurine-Rich Cuttlefish (Sepia officinalis) Extract Against Hydrogen Peroxide-Induced Oxidative Stress in SH-SY5Y Cells.

Oxidative stress mediates the cell damage in several neurodegenerative diseases, some of which are Alzheimer's disease (AD), multiple sclerosis and Parkinson's disease (PD). In this study, we investigated whether the taurine-rich cuttlefish extract could exert a protective effect on damaged human neuroblastoma SH-SY5Y cells induced by hydrogen peroxide (H2O2). Our results revealed that pre-treatment with cuttlefish extract effectively increased the cell viability by protecting the cells from intracellular reactive oxygen species (ROS) induced by H2O2 exposure. Furthermore, apoptosis related proteins Bcl-2 and Bax were investigated by western-blot analysis and results indicated that cuttlefish extract promoted the expression of anti-apoptotic Bcl-2 protein while inhibiting the expression of pro-apoptotic Bax protein. Therefore, cuttlefish extract containing the ability of scavenging excessive ROS, the capacity of anti-oxidative stress, could be employed in neurodegenerative disease prevention. In conclusion, the results suggest that cuttlefish extract could be used as a potential candidate for preventing several human neurodegenerative and other disorders caused by oxidative stress.

Fermented Asterina pectinifera with Cordyceps militaris Mycelia Induced Apoptosis in B16F10 Melanoma Cells.

This prime objective of this study was to explore the anti-cancer activity of fermented Asterina pectinifera with Cordyceps militaris mycelia (FACM) in B16F10 murine melanoma cells. The effect of FACM on cell viability was assessed using MTT assay. Furthermore, the effect of FACM was compared with unfermented A. pectinifera on cell viability. The results demonstrated that the fermented FACM extract has a higher inhibitory activity on the proliferation of B16F10 murine melanoma cells than unfermented A. pectinifera. In addition, FACM also promoted the expression of pro-apoptotic protein Bax leading to stimulate apoptosis in B16F10 cells. Therefore the present study demonstrates that the FACM might be a potential effective anti-cancer agent, as a result of its stronger anti-proliferative effect and apoptosis inducing effect than A. pectinifera or C. militaris on melanoma cells.

Antioxidant Activity of Extract from the Cephalothorax of Fenneropenaeus chinensis.

We investigated the antioxidant activity of taurine rich water extract from the cephalothorax of Fenneropenaeus chinensis (FCC). The antioxidant potency of water extract from FCC was assessed using various assay methods, such as DPPH (1,1-diphenyl-2-picrylhydrazyl), alkyl radical scavenging activity, ABTS (2,2'-azinobis (3-ethylbenzothiazoline 6-sulfonic acid ammonium salt)) radical scavenging activity and Ferric reducing antioxidant power (FRAP) assay. The DPPH and alkyl radical scavenging activities of FCC were dose-dependently increased. The lipid peroxidation was estimated using ferric thiocyanate (FTC) assay and thiobarbituric acid (TBA) methods. However, a higher lipid peroxidation activity was observed in TBA method than FTC method. The results of the present study suggested that the FCC extract potentially scavenged the free radical and reduced oxidative stress. Therefore, the present study is concluded that the FCC extract could be a potential source of antioxidant activity.

Antioxidant Effect of Taurine-Rich Paroctopus dofleini Extracts Through Inhibiting ROS Production Against LPS-Induced Oxidative Stress In Vitro and In Vivo Model.

Taurine is an essential amino acid to improve the function of cardiovascular, skeletal muscle, retina, and central nervous system. It also plays a role as an antioxidant agent against reactive oxygen species (ROS) generated by various substances. The aim of the current study was to examine the antioxidant capacity of water extracts of Paroctopus dofleini. Radical scavenging activity of P. dofleini extracts was performed using an ESR spectrophotometer. Protective effects of P. dofleini extracts against lipopolysaccharide (LPS)-induced oxidative stress in RAW264.7 cells were evaluated using flow cytometry. The P. dofleini extracts showed a potent antioxidant activity against LPS-induced oxidative stress on RAW264.7 cells. Furthermore, the in vivo antioxidant activity of P. dofleini extract on LPS-induced oxidative stress was assessed using zebrafish embryos. P. dofleini successfully scavenged the LPS-induced intracellular ROS and prevented lipid peroxidation in zebrafish embryos. The results obtained in this study clearly demonstrate that the P. dofleini significantly scavenge the ROS and prevent lipid peroxidation in both in vitro and in vivo models.

Taurine Attenuates Doxorubicin-Induced Toxicity on B16F10 Cells.

This study aimed to investigate the effect of doxorubicin co-treatment with taurine on B16F10 melanoma cells. Frequently, Doxorubicin is used in the treatments of many different kinds of cancers, some of which are soft tissue sarcomas, hematological malignancies and carcinomas. However, the clinical application of doxorubicin is compromised by its severe adverse effects, including cardiotoxicity. In the present study, the efficacy of doxorubicin co-treatment with taurine was investigated. B16F10 cell viability was evaluated using MTT assays, trypan blue dye exclusion assays, and fluorescent staining technique. Apoptotic cells were detected by flow cytometry and the proteins associated with apoptosis and cellular differentiations were assessed by immunoblotting. Doxorubicin inhibited cell growth and induced cell death in B16F10 cells. Interestingly, doxorubicin co-treatment with taurine inhibited apoptosis in B16F10 cells. These results indicate that doxorubicin co-treatment with taurine attenuates doxorubicin-induced cytotoxicity and reduces ROS production in B16F10 cells.

Taurine Attenuates Epithelial-Mesenchymal Transition-Related Genes in Human Prostate Cancer Cells.

Prostate cancer is the most common non-cutaneous cancers among men and the second leading cause of cancer-related deaths among men. Aberrant activation of the epithelial to mesenchymal transition (EMT) has been exhibited to be one of the most common causes of treatment failure and death in cancer patients. In cancer cells with metastatic competence, the E-cadherin switch is a well-established hallmark. Suppression of E-cadherin through its transcriptional repressor SNAIL is thus a determining factor for EMT. TWIST1 is an important transcription factor in EMT, which is present under both physiologic (embryogenesis) and pathologic (metastasis) conditions, and enhances the invasiveness and migration ability of cells. In this study, we investigated the inhibitory effects of taurine on EMT-related genes, such as E-cadherin, N-cadherin, TWIST1, ZEB1, SNAIL, and vimentin. EMT markers were detected by RT-PCR and western blotting. The results showed that taurine down-regulated the expression of N-cadherin, TWIST1, ZEB1, SNAIL, and vimentin. In contrast, taurine increased E-cadherin expression. Our findings indicate that taurine has EMT inhibitory effects on human prostate cancer cells.

Protective Effect of Taurine on Mice with Doxorubicin-induced Acute Kidney Injury.

Nephrotic syndrome is still a therapeutic challenge because an effective treatment has not been developed. Evidence suggests that multidrug therapy is more effective than monotherapy in amelioration of renal injury. Therefore, we examined if taurine exerts a protective effect on doxorubicin-induced acute kidney injury in mice. Eight-week-old male Balb/c nude mice were used in this study. Taurine was orally administered at a dose of 50 mg/kg and 100 mg/kg body weight for 5 days. In the meantime, the mice were administered intraperitoneal injections of doxorubicin at 15 mg/kg body weight. At 24 h after the doxorubicin challenge, the response in the taurine-treated mice was compared with that in the vehicle-treated control mice. The doxorubicin-induced acute kidney injury model displayed a significant increase in the renal expression of apoptosis-related proteins (p53, phospho-p53, caspase 9, and caspase 3), whereas in the taurine-treated mice, the augmented expression of renal inflammation-related mRNAs such as NF-kB, COX-2, and iNOS was down-regulated. These results suggest that taurine acts as a renoprotective agent by inhibiting apoptosis and inflammation in the kidney of mice with doxorubicin-induced renal injury.

Moringa oleifera from Cambodia Ameliorates Oxidative Stress, Hyperglycemia, and Kidney Dysfunction in Type 2 Diabetic Mice.

Recent reports have shown the antidiabetic effect of Moringa oleifera from various parts of the world. However, M. oleifera from Cambodia has never determined. Therefore, the aim of this study was to assess the antidiabetic effect of M. oleifera extract from Cambodia. The leaf ethanolic extract contained flavonoids (31.90 mg/mL), polyphenols (53.03 mg/mL), lycopene (0.042 mg/mL), and ß-carotene (0.170 mg/mL), and possessed 2,2-diphenyl-1-picrylhydrazyl, hydrogen peroxide, and hydroxyl radical scavenging activities of 92.40, 99.25, and 83.57 TE/µM at 1 mg/mL, respectively. Db/db mice were orally administered the leaf extract (150 mg/kg/day) for 5 weeks. M. oleifera treatment significantly ameliorated the altered fasting plasma glucose (from 483 to 312 mg/dL), triglyceride (from 42.12 to 23.00 mg/dL), and low-density lipoprotein cholesterol (from 107.21 to 64.25 mg/dL) compared to control group, and increased the insulin levels from 946 ± 92 to 1678 ± 268 pg/mL. The histopathological damage and expression levels of tumor necrosis factor-alpha, interleukin (IL)-1ß, IL-6, cyclooxygenase-2, and inducible nitric oxide synthase in renal tissue decreased. These results indicate the potential antidiabetic benefits of M. oleifera ethanolic leaf extract.

Immune-Stimulatory Effects of Althaea rosea Flower Extracts through the MAPK Signaling Pathway in RAW264.7 Cells.

Althaea rosea (Linn.) is a medicinal plant from China and Korea that has been traditionally used to control inflammation, to stop bedwetting and as a mouthwash in cases of bleeding gums. Its flowers are employed medicinally for their emollient, demulcent and diuretic properties, which make them useful in chest complaints. Furthermore, a flower extract decoction is used to improve blood circulation, for the treatment of constipation, dysmenorrhoea, haemorrhages, etc. However, the possible mechanisms of the immune-stimulatory effect remains to be elucidated. Therefore, we investigated the role of Althaea rosea flower (ARF) extracts in the immune-stimulatory effect of macrophages and the underlying mechanisms of action. ARF water extract (ARFW) could dose-dependently increase NO production and cytokines (IL-6 and TNF-α). We also found that ARFW significantly increased the expression of iNOS and COX-2 proteins in RAW264.7 cells. Consistent with these results, MAPK protein (JNK, ERK, p38) expression levels were induced after treatment with ARFW. Additionally, ARFW showed a marked increase in the phosphorylation level of IκBα and subsequent IκBα degradation allowing NF-κB nuclear translocation. These results suggest that the immune-stimulatory effect of A. rosea flower extracts is mediated through the translocation of NF-κB p65 subunit into the nucleus from the cytoplasm and subsequent activation of pro-inflammatory cytokines (IL-6 and TNF-α) and other mediators (iNOS and COX-2), which occurs mainly through MAPK signalling pathway. Thus, we suggest that ARFW could be considered as a potential therapeutic agent useful in the development of immune-stimulatory compounds.

Biosynthesis of Oligomeric Anthocyanins from Grape Skin Extracts.

We synthesized oligomeric anthocyanins from grape skin-derived monomeric anthocyanins such as anthocyanidin and proanthocyanidin by a fermentation technique using Aspergillus niger, crude enzymes and glucosidase. The biosyntheses of the oligomeric anthocyanins carried out by the conventional method using Aspergillus niger and crude enzymes were confirmed by ESI-MS. The molecular weight of the synthesized anthocyanin oligomers was determined using MALDI-MS. The yield of anthocyanin oligomers using crude enzymes was higher than that of the synthesis using Aspergillus fermentation. Several studies have been demonstrated that oligomeric anthocyanins have higher antioxidant activity than monomeric anthocyanins. Fermentation-based synthesis of oligomeric anthocyanins is an alternative way of producing useful anthocyanins that could support the food industry.