Wen Chi Hou

Wogonin and fisetin induce apoptosis in human promyeloleukemic cells, accompanied by a decrease of reactive oxygen species, and activation of caspase 3 and Ca2+-dependent endonuclease

Seven structurally related flavonoids including luteolin, nobiletin, wogonin, baicalein, apigenin, myricetin and fisetin were used to study their biological activities on the human leukemia cell line, HL-60. On MTT assay, wogonin, baicalein, apigenin, myricetin and fisetin showed obvious cytotoxic effects on HL-60 cells, with wogonin and fisetin being the most-potent apoptotic inducers among them. The cytotoxic effects of wogonin and fisetin were accompanied by the dose- and time-dependent appearance of characteristics of apoptosis including DNA fragmentation, apoptotic bodies and the sub-G1 ratio. Treatment with an apoptosis-inducing concentration of wogonin or fisetin causes rapid and transient induction of caspase 3/CPP32 activity, but not caspase 1 activity. Further, cleavage of poly(ADP-ribose) polymerase (PARP) and decrease of pro-caspase 3 protein were detected in wogonin- and fisetin-treated HL-60 cells. An increase in the pro-apoptotic protein, bax, and a decrease in the anti-apoptotic protein, Mcl-1, were detected in fisetin- and wogonin-treated HL-60 cells. However, Bcl-2, Bcl-XL, and Bad all remained unchanged in wogonin- and fisetin-treated HL-60 cells. In vitro chromatin digestion revealed that endonuclease activity was profoundly enhanced in wogonin- and fisetin-treated HL-60 cells, and the addition of ethylenediaminetetraacetic acid (EDTA) or ethyleneglycoltetraacetic acid (EGTA) into the reaction blocked endonuclease activation and at an optimum pH of 7.5. The caspase 3 inhibitor, Ac-DEVD-CHO, but not the caspase 1 inhibitor, Ac-YVAD-CHO, attenuated wogonin- and fisetin-induced DNA ladders, PARP cleavage, and endonuclease activation. Pretreatment of HL-60 cells with N-acetyl-cysteine or catalase efficiently inhibited H(2)O(2) (200 microM)-induced apoptosis, but showed no inhibitory effect on wogonin- and fisetin-induced DNA ladders, caspase 3 activation, or bax protein induction. Decrease in endogenous ROS production was detected in wogonin- and fisetin-treated HL-60 cells by DCHF-DA assay. In conclusion, our experiments indicate that a decrease in intracellular peroxide level was involved in wogonin- and fisetin-induced apoptosis; activation of caspase 3 and endonuclease, induction of bax protein and suppression of Mcl-1 protein were detected in the process.

Free radical-scavenging activity of Taiwanese native plants

The 70% aqueous acetone extracts of ten Taiwanese native plants were evaluated by various antioxidant assays, including 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl (.OH) radicals, and reducing power assay. In the present study, extracts of Acer buerferianum var. formosanum, Cleyera japonica var. morii, Cyclobalanopsis stenophylla var. stenophylloides, and Machilus zuihoensis exhibited stronger activity against DPPH radicals, and their IC50 values ranged from 5.4 to 8.3 microg/ml. The ten selected extracts effectively inhibited the formation of .OH generated in the Fenton reaction system. Among the extracts whose reducing power activities were determined, A. buerferianum var. formosanum, C. japonica var. morii, C. stenophylla var. stenophylloides, Eriobotrya deflex, and M. zuihoensis showed high activity. The results indicate the 70% aqueous acetone extracts of A. buerferianum var. formosanum, C. japonica var. morii, C. stenophylla var. stenophylloides, and M. zuihoensis with great potency in these assay systems and may be candidates for the development of natural antioxidants.

Antioxidant, anti-semicarbazide-sensitive amine oxidase, and anti-hypertensive activities of geraniin isolated from Phyllanthus urinaria

The wrinkle-fruited leaf flower (Phyllanthus urinaria L.) (Euphorbiaceae) is widely used as a traditional folk medicine for inflammatory relief. Geraniin, the hydrolysable tannin, was purified by a series of chromatographic processes from the 70% aqueous acetone extracts of P. urinaria and identified by NMR [1H (500 MHz) and 13C NMR (126 MHz)] spectra and mass spectroscopy. The scavenging activities of geraniin against DPPH radicals (half-inhibition concentration, IC50, were 0.92 and 1.27 microM, respectively, for pH 4.5 and pH 7.9), hydroxyl radicals (IC50 was 0.11 microM by deoxyribose method and 1.44 microM by electron spin resonance method), and superoxide radicals (IC50 were 2.65 microM) were determined in comparison with positive controls. The inhibitory activities against xanthine oxidase (IC50 were 30.49 microM) were measured. Geraniin also showed dose-dependent inhibitory activities against semicarbazide-sensitive amine oxidase (SSAO, IC50 were 6.58 microM) and against angiotensin converting enzyme (ACE, IC50 were 13.22microM). For kinetic property determinations, geraniin showed competitive inhibitions against SSAO (the apparent inhibition constant, Ki, was 0.70microM) and mixed noncompetitive inhibitions against ACE. Spontaneously hypertensive rats (SHR, 10-week age) were orally administered to once (5 mg geraniin/kg SHR), and changes of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured over 24 h and compared with the positive control of captopril (2 mg/kg SHR). The geraniin showed antihypertensive activity in lowering SBP and DBP and showed a significant difference from the blank (distilled water) at 2, 4, 6, 8, and 24 h. Healthy food products could use geraniin for antioxidant protection and therapeutic effects in the future.

Heme oxygenase-1 inhibits breast cancer invasion via suppressing the expression of matrix metalloproteinase-9

In the present study, we investigated the antitumor effects of the invasiveness and migration of heme oxygenase 1 (HO-1) in human breast carcinoma cells. 12-O-tetradecanoylphorbol-13-acetate (TPA)–induced matrix metalloproteinase-9 (MMP-9) enzyme activity and gene expression at both protein and mRNA levels were examined in human breast carcinoma cells (MCF-7 and MDA-MB-231), and the addition of the MMP-9 inhibitor, SB3CT, significantly suppressed TPA-induced invasion and migration according to the in vitro Transwell assay. Elevation of HO-1 gene expression by ferric protoporphyrin IX inhibited TPA-induced invasion of MCF-7 cells, which was blocked by adding the heme oxygenase inhibitor, tin protoporphyrin IX, or transfection of cells with HO-1 short hairpin RNA. MCF-7 cells overexpressing HO-1 (MCF-7/HO-1) were established in the present study, and TPA-induced MMP-9 gene expression, tumor invasion, and colony formation were significantly reduced in MCF-7/HO-1 cells, compared with those in Neo-transfected cells. Activation of protein kinase Cα/extracellular signal-regulated kinases/AP-1 with stimulation of reactive oxygen species production was involved in TPA-induced invasion of MCF-7 cells, which was attenuated by HO-1 protein induced by ferric protoporphyrin IX or transfection of HO-1 expression vectors. Additionally, the addition of carbon monoxide, but not ferric ions, biliverdin, or bilirubin, inhibited TPA-induced invasion through suppressing MMP-9, extracellular signal-regulated kinases, and AP-1 activation stimulated by TPA. The beneficial role of HO-1 in blocking tumor invasion was first identified in this study. [Mol Cancer Ther 2008;7(5):1195–1206]

Anti-Inflammatory Activities of Cinnamomum cassia Constituents In Vitro and In Vivo

We have investigated the anti-inflammatory effects of Cinnamomum cassia constituents (cinnamic aldehyde, cinnamic alcohol, cinnamic acid, and coumarin) using lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) and carrageenan (Carr)-induced mouse paw edema model. When RAW264.7 macrophages were treated with cinnamic aldehyde together with LPS, a significant concentration-dependent inhibition of nitric oxide (NO), tumor necrosis factor (TNF-α), and prostaglandin E2 (PGE2) levels productions were detected. Western blotting revealed that cinnamic aldehyde blocked protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nuclear transcription factor kappa B (NF-κB), and IκBα, significantly. In the anti-inflammatory test, cinnamic aldehyde decreased the paw edema after Carr administration, and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the paw tissue. We also demonstrated cinnamic aldehyde attenuated the malondialdehyde (MDA) level and myeloperoxidase (MPO) activity in the edema paw after Carr injection. Cinnamic aldehyde decreased the NO, TNF-α, and PGE2 levels on the serum level after Carr injection. Western blotting revealed that cinnamic aldehyde decreased Carr-induced iNOS, COX-2, and NF-κB expressions in the edema paw. These findings demonstrated that cinnamic aldehyde has excellent anti-inflammatory activities and thus has great potential to be used as a source for natural health products.

Antioxidant and anti-inflammatory properties of Cardiospermum halicacabum and its reference compounds ex vivo and in vivo.

AIMS OF THE STUDY Cardiospermum halicacabum (CH) has been used in Chinese medicine for a long time. However, its fingerprint chromatogram, antioxidant, anti-inflammatory effects and mechanism are still needed to be explored. Therefore, the aims of this study investigated the antioxidant and anti-inflammatory effects of CH extracts and its reference compounds ex vivo and in vivo. MATERIALS AND METHODS In HPLC analysis, the fingerprint chromatogram of ethanolic extract of CH (ECH) was established. The effects of ACH (aqueous extract of CH) and ECH extracts were assessed for the antioxidant and LPS-induced NO production in RAW264.7 cells. In vivo anti-inflammatory activities of ECH were evaluated in mouse paw edema induced by λ-carrageenan (Carr). We investigate the anti-inflammatory mechanism of ECH via studies of the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the liver and the levels of malondialdehyde (MDA) and nitrite oxide (NO) in the edema paw. Serum NO and TNF-α were also measured. RESULTS ECH had better antioxidant activity than that of ACH. In the anti-inflammatory test, ECH inhibited the development of paw edema induced by Carr and increased the activities of CAT, SOD and GPx in the liver tissue. ECH also decreased the level of NO in edematous paw tissue and in serum level, and diminished the level of serum TNF-α at the fifth hour after Carr injection. CONCLUSIONS ECH exerts anti-inflammatory effects by suppressing TNF-α and NO. The anti-inflammatory mechanism of ECH might be related to the decrement of the level of MDA in the edema paw via increasing the activities of CAT, SOD and GPx in the liver. The results showed that ECH might serve as a natural antioxidant and anti-inflammatory agent.

Analgesic Effects and the Mechanisms of Anti-inflammation of Ergostatrien-3β-ol from Antrodia camphorata Submerged Whole Broth in Mice

Ergostatrien-3beta-ol (ST1), an active and major ingredient from Antrodia camphorata (AC) submerged whole broth was evaluated for the analgesic and anti-inflammatory effects. Treatment of male imprinting control region (ICR) mice with ST1 (1, 5, and 10 mg/kg) significantly inhibited the numbers of acetic-acid-induced writhing response in 10 min. Also, our result showed that ST1 (10 mg/kg) significantly inhibited the formalin-induced pain in the late phase (p < 0.001). In the anti-inflammatory test, ST1 (10 mg/kg) decreased the paw edema at 4 and 5 h after lambda-carrageenin (Carr) administration and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the liver tissue. We also demonstrated that ST1 significantly attenuated the malondialdehyde (MDA) level in the edema paw at 5 h after Carr injection. ST1 (1, 5, and 10 mg/kg) decreased the nitric oxide (NO) levels on both the edema paw and serum level at 5 h after Carr injection. Also, ST1 (5 and 10 mg/kg) diminished the serum tumor necrosis factor (TNF-alpha) at 5 h after Carr injection. Western blotting revealed that ST1 (10 mg/kg) decreased Carr-induced inducible nitric oxide synthase (iNOS), and cycloxyclase (COX-2) expressions at 5 h in the edema paw. An intraperitoneal (ip) injection treatment with ST1 also diminished neutrophil infiltration into sites of inflammation, as did indomethacin (Indo). The anti-inflammatory mechanisms of ST1 might be related to the decrease in the level of MDA, iNOS, and COX-2 in the edema paw via increasing the activities of CAT, SOD, and GPx in the liver through the suppression of TNF-alpha and NO.

Molecular cloning of two metallothionein-like protein genes with differential expression patterns from sweet potato (Ipomoea batatas) leaves

Metallothionein (MT) is a group of proteins with low molecular masses and high cysteine contents, and is classified into different types, which in general contains two domains (domain 1 and domain 2) with typical amino acid sequences (Rauser 1999). In this report two full-length cDNAs (Y459 and G14) encoding MT-like proteins were isolated from leaves of sweet potato (Ipomoea batatas). Their open reading frames contained 249 and 195 nucleotides (82 and 64 amino acids) for Y459 and G14, respectively, and exhibited a relatively low amino acid sequence similarity (ca. 25.8%). Gene structure studies showed that Y459 had the conserved domain 1 region of type 2 MT; however, the domain 2 region was not conserved and contained additional amino acids between the CxC and CxC spacing. G14 had conserved domains 1 and 2 of type 4 MT except that the last CxC of domain 2 was changed to RxC. Semi-quantitative RT-PCR showed that Y459 was expressed in significant quantity in roots and stems, but was much less in green leaves. During natural and induced (with dark and ethephon, an ethylene-releasing compound, treatments) leaf senescence, Y459 gene expression was significantly enhanced. In contrast, relatively constant gene expression levels were found for G14 in all tissues or treatments analyzed. In conclusion, the two MT-like protein genes of sweet potato display differential gene structures and gene expression patterns, which may be associated with the diverse roles and functions they play in plant physiology in order to cope with particular developmental and environmental cues.

Flavanones structure-related inhibition on TPA-induced tumor promotion through suppression of extracellular signal-regulated protein kinases: Involvement of prostaglandin E2 in anti-promotive process

Biological functions of flavanones have been studied extensively, however, the structure‐related activities of flavanones on 12‐o‐tetradecanoylphorbol 13‐acetate (TPA)‐induced promotive effects are still unclear. In this study, flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone showed the most significant dose‐dependent inhibition on TPA‐induced proliferative effects among eight tested flavanones in NIH3T3 cells. TPA‐induced mitogen activated protein kinases (MAPK) phosphorylation, ornithine decarboxylase (ODC), c‐Jun, and cyclooxygenase 2 (COX‐2) protein expressions in a time‐dependent manner, and the maximal inductive time point is at 1 h for MAPK phosphorylation and 6 h for others. Flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone showed the dose‐dependent inhibition on TPA‐stimulated MAPK phosphorylation, COX‐2, ODC, c‐Jun protein expressions. Induction of, prostaglandin E2 (PGE2) production was detected in TPA‐treated NIH3T3 cells, and flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone inhibited significantly PGE2 production induced by TPA. Addition of PGE2 reverses the inhibitory activities of flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone on TPA‐induced proliferation. And, PD98059, a specific inhibitor of ERKs, inhibited TPA‐induced MAPK phosphorylation, accompanied by decreasing COX‐2, c‐Jun, and ODC protein expression, and showed dose‐dependent inhibition on TPA‐induced proliferation in cells. These results demonstrated that PGE2 is an important mediator in TPA‐induced proliferation, and MAPK phosphorylation was located at the upstream of COX‐2, c‐Jun, and ODC gene expressions in TPA‐induced responses. Furthermore, flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone (100 μM) suppressed TPA‐induced colony formation associated with blocking MAPK phosphorylation, ODC, c‐Jun, and COX‐2 proteins expression. And, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assay showed that flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone did not perform potent anti‐radical activities among these eight tested compounds. In conclusion, this study provided molecular evidences to demonstrate that flavanone, 2′‐OH flavanone, 4′‐OH flavanone, 6‐OH flavanone were potent inhibitors on TPA‐induced responses without notable cytotoxicity through suppression of PGE2 production; and anti‐radical activity of flavanones was not correlated with preventing the occurrence of tumor promotion. We proposed that blocking TPA‐induced intracellular signaling responses might be involved in the anti‐promotive mechanism of flavanones. J. Cell. Physiol. 193: 93–102, 2002.

Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Participate in Anti-inflammatory Activity of Imperatorin from Glehnia littoralis

In this study, we have investigated the anti-inflammatory effects of imperatorin, a compound isolated from the roots of Glehnia littoralis, using a lipopolysaccharide (LPS)-stimulated mouse macrophage (RAW264.7) in vitro and a carrageenan (Carr)-induced mouse paw edema model in vivo. When RAW264.7 macrophages were treated with imperatorin together with LPS, a significant concentration-dependent inhibition of NO production was detected. Western blotting revealed that imperatorin blocked the protein expression of iNOS and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW264.7 macrophages significantly. In the anti-inflammatory test, imperatorin decreased the paw edema at 4 and 5 h after Carr administration and increased the activities of catalase, superoxide dismutase, and glutathione peroxidase in paw edema. We also demonstrated that imperatorin significantly attenuated the malondialdehyde level in the edema paw at the fifth hour after Carr injection. Imperatorin decreased the NO and tumor necrosis factor and prostaglandin E2 levels on serum at 5 h after Carr injection. Western blotting revealed that imperatorin decreased Carr-induced iNOS and COX-2 expressions at 5 h in edema paw. An intraperitoneal injection treatment with imperatorin also diminished neutrophil infiltration into sites of inflammation as did indomethacin. The results suggested that imperatorin had anti-inflammatory effects in LPS-stimulated RAW 264.7 cells and Carr-injected mice, respectively. In addition, inhibition of elevated iNOS and COX-2 protein expression as well as neutrophil infiltration of Carr-injected paws may be involved in the beneficial effects of imperatorin.