Gallant Chan - Academia.edu (original) (raw)

Papers by Gallant Chan

Research paper thumbnail of Quality Control on Herbal Medicine and Its Application

Evidence-Based Complementary and Alternative Medicine, 2018

Research paper thumbnail of Molecular studies of the vascular endothelial growth factor (Vegf-A) and VEGF-receptor (Flk-1) genes of grass carp

... by Chan Kar Lun Gallant April 2005 ... Apart from its adaptive role in hypoxia, VEGF is an im... more ... by Chan Kar Lun Gallant April 2005 ... Apart from its adaptive role in hypoxia, VEGF is an important angiogenic factor in various estrogen target tissues such as the placenta (Pepe and Albrecht, 1999), pituitary (Ochoa et al., 2000), testis (Rudolfsson et al., 2004), ovary and uterus ...

Research paper thumbnail of Molecular Interaction between Andrographolide and Glutathione Follows Second Order Kinetics

Chemical and Pharmaceutical Bulletin, 2008

The intracellular level of glutathione (GSH) was significantly decreased after the addition of an... more The intracellular level of glutathione (GSH) was significantly decreased after the addition of andrographolide (1) to cell cultures of HepG2. When the molecular interaction between andrographolide and GSH was investigated under a condition mimicking the in vivo environment, we observed that the level of GSH dropped in the presence of andrographolide. Stoichiometric analysis indicates that the reaction between these two reactants was 1 to 1 at pH 7 and followed second order kinetics. The activation energy of the overall reaction was 41.9؎10 kJ • mol ؊1 according to the Arrhenius equation. Using a micro-liquid-liquid extraction method followed by micellar electrokinetic chromatographic separation, two major products were isolated and identified, and their chemical structures were determined as 14-deoxy-12-(glutathione-amino)-andrographolide (2) and 14deoxy-12-(glutathione-S-yl)-andrographolide (3). Based on these structural findings, a hypothetical mechanism of reaction between glutathione and andrographolide was proposed. It is concluded that the a a,b b-unsaturated lactone moiety of andrographolide reacts with GSH through a Michael addition followed by dehydration of the adduct.

Research paper thumbnail of Searching for Active Ingredients in Edible Bird’s Nest

Journal of Complementary Medicine & Alternative Healthcare, 2018

Glycoprotein-A Longmystery on EBN Protein comprised the largest part of EBN, over half of the nes... more Glycoprotein-A Longmystery on EBN Protein comprised the largest part of EBN, over half of the nest made of protein. However, the proteomics study was hindered by several limitations. The heavily glycosylated chains of peptide polymer in EBN were very difficult to be hydrolyzed, and thus the rooms for enzymatic reactions were always limited. The first report of protein on EBN, published in 1975 by a French group, indicated that the protein of EBN was actually glycoprotein [14].

Research paper thumbnail of Redox regulation by andrographolide induced cell cycle arrest and cell death in HepG2 cells

Research paper thumbnail of An Optimized Extract, Named Self-Growth Colony, from Platelet-Rich Plasma Shows Robust Skin Rejuvenation and Anti-Ageing Properties: A Novel Technology in Development of Cosmetics

Skin Pharmacology and Physiology, 2021

Introduction: Inspired by application of platelet-rich plasma (PRP) in skin treatment during inju... more Introduction: Inspired by application of platelet-rich plasma (PRP) in skin treatment during injuries, an extracting method was developed here to recover high amounts of cytokines and growth factors from PRP; this prepared extract was named as self-growth colony (SGC). Methods: In optimization of SGC preparation, various parameters were tested, for example, centrifugation force, freeze-thaw, sonication, and inclusion of calcium chelator. The amounts of cytokines and growth factors, including platelet factor 4, β-thromboglobulin, epidermal growth factor, vascular endothelial growth factor, platelet-derived growth factor, were measured by ELISA assay. Results: By comparing to PRP, the prepared SGC contained a significant higher amount of measured growth factors. In addition, the degradation of growth factors within SGC during the storage was calibrated, which showed better stability as compared to that of PRP preparation. Having possible application in skin care, the optimized SGC was...

Research paper thumbnail of The binding of kaempferol-3-O-rutinoside to vascular endothelial growth factor potentiates anti-inflammatory efficiencies in lipopolysaccharide-treated mouse macrophage RAW264.7 cells

Phytomedicine, 2021

Reported cases encountered difficulty in differentiating between inflammatory carcinoma and breas... more Reported cases encountered difficulty in differentiating between inflammatory carcinoma and breast edema caused by congestive heart failure especially if the breast edema is unilateral. Our presented case is an elderly woman with unilateral breast edema due to congestive heart failure that was initially suspected to have breast cancer based on clinical findings. However imaging studies showed breast edema pattern with no definite underlying mass. This edema was resolved with standard treatment of heart failure. Congestive heart failure may be a possible cause of unilateral breast edema especially in a patient with background of congestive heart failure.

Research paper thumbnail of The anti-bacterial effects of aerial parts of Scutellaria baicalensis: Potential application as an additive in aquaculture feedings

Aquaculture, 2020

The root of Scutellaria baicalensis (Scutellaria Radix) is a medicinal part being used as a herba... more The root of Scutellaria baicalensis (Scutellaria Radix) is a medicinal part being used as a herbal drug; while its stem and leaf (aerial part) are considered as waste. Several reports have shown that aerial part of S. baicalensis (SBA) has chemical similarity with its root, suggesting the possible usage of this non-medicinal part. Thus, the usage of SBA as an additive in aquaculture feeding could be a new way to recycle the waste. The water extract of SBA inhibited the growth of several common pathogenic bacteria in aquaculture, e.g. Aeromonas hydrophila, Edwardsiella tarda, Vibrio alginolyticus and Vibrio harveyi. In cultured macrophage cells (RAW 264.7), application of SBA extract showed strong anti-inflammation effect, which inhibited the expression of inflammatory cytokine, i.e. IL-1β, as induced by LPS. Similarly, SBA extract suppressed the LPS-induced transcriptional activity mediated by NF-κB. When applied in fish aquaculture, the extract of SBA was mixed into the feedings of Siganus fuscescens (rabbit fish) that was cultured with a mixture of pathogenic bacteria. The expression levels of COX-2, IL-1β and TNF-α were markedly reduced in the present of SBA extract. Our investigations show the anti-bacterial effect of SBA extract, as well as its potential anti-inflammation effects both in vitro and in vivo, which therefore suggest the possible development of S. baicalensis aerial part in fish aquaculture.

Research paper thumbnail of Kaempferol, a Major Flavonoid in Ginkgo Folium, Potentiates Angiogenic Functions in Cultured Endothelial Cells by Binding to Vascular Endothelial Growth Factor

Frontiers in Pharmacology, 2020

Kaempferol is a major flavonoid in Ginkgo Folium and other edible plants, which is being proposed... more Kaempferol is a major flavonoid in Ginkgo Folium and other edible plants, which is being proposed here to have roles in angiogenesis. Angiogenesis is important in both physiological and pathological development. Here, kaempferol was shown to bind with vascular endothelial growth factor (VEGF), probably in the heparin binding domain of VEGF: this binding potentiated the angiogenic functions of VEGF in various culture models. Kaempferol potentiated the VEGF-induced cell motility in human umbilical vein endothelial cells (HUVECs), as well as the sub-intestinal vessel sprouting in zebrafish embryos and formation of microvascular in rat aortic ring. In cultured HUVECs, application of kaempferol strongly potentiated the VEGF-induced phosphorylations of VEGFR2, endothelial nitric oxide synthase (eNOS) and extracellular signal-regulated kinase (Erk) in time-dependent and concentration-dependent manners, and in parallel the VEGFmediated expressions of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were significantly enhanced. In addition, the potentiation effect of kaempferol was revealed in VEGF-induced migration of skin cell and monocyte. Taken together, our results suggested the pharmacological roles of kaempferol in potentiating VEGF-mediated functions should be considered.

Research paper thumbnail of Isoorientin derived from Gentiana veitchiorum Hemsl. flowers inhibits melanogenesis by down-regulating MITF-induced tyrosinase expression

Phytomedicine, 2018

Background: Gentiana is a genus of flowering plants in Gentianaceae family, which comprises of 1,... more Background: Gentiana is a genus of flowering plants in Gentianaceae family, which comprises of 1,600 species. The roots of few species of Gentiana, also known as Long Dan Cao in Chinese, are traditionally used in herbal remedies for a wide variety of liver-associated diseases. The medicinal part of Gentiana is root; however, the trumpet-shaped flowers are seldom being used. Purpose: We investigated the anti-melanogenesis effect of water extract of Gentiana veitchiorum Hemsl. flowers, and isoorientin was identified to be the active compound. Study design: We tested the anti-melanogenesis effects of extracts deriving from different parts of G. veitchiorum, followed by identification of active ingredients within the extracts. The mechanism of inhibitory effect on melanogenesis, triggered by isoorientin, was elucidated by in vitro analyses. Methods: HPLC was applied to identify the components in water extracts from different parts of G. veitchiorum. The cytotoxicity of extracts and pure compounds in cultured B16F10 murine melanoma cells was determined by MTT and trypan blue assays. Melanin assay, tyrosinase assay, RT-PCR, luciferase assay and western blot were used to analyze the effect of isoorientin in melanin content, tyrosinase activity, as well as the expressions of those related genes and proteins. Results: We identified an inhibitory effect on melanogenesis from water extract of G. veitchiorum flowers in B16F10 cells. Isoorientin, a major flavone in the extract, was identified to be an active ingredient causing reduction in melanin content in a dose-dependent manner. Such reduction was suggested to be a result of suppressed expression of tyrosinase (TYR), tyrosinase related protein-1 (TRP1) and DOPA-chrome tautomerase (DCT). Isoorientin also suppressed the expression of microphthalmia-associated transcription factor (MITF) through the phosphorylation of cAMP response element-binding protein (CREB). Conclusion: These findings indicate that isoorientin derived from G. veitchiorum flowers may be a potential skin lightening agent for the treatment of skin pigmentary disorders. monophosphate (cAMP)-mediated microphthalmia-associated transcription factor (MITF). MITF is a basic helix-loop-helix leucine zipper transcription factor playing a key role in melanocyte differentiation, and which is also a master activator in triggering the expression of various melanin synthesizing enzymes through binding to E-box sequence (Busca and Ballotti, 2000; Hartman and Czyz, 2014). Melanin synthesis is a multi-step process in which tyrosinase is a key enzyme as

Research paper thumbnail of The extract of Polygoni Cuspidati Rhizoma et Radix suppresses the vascular endothelial growth factor-induced angiogenesis

Phytomedicine : international journal of phytotherapy and phytopharmacology, Jan 15, 2018

Polygoni Cuspidati Rhizoma et Radix (PCRR; the root and rhizome of Polygonum cuspidatum Sieb. et ... more Polygoni Cuspidati Rhizoma et Radix (PCRR; the root and rhizome of Polygonum cuspidatum Sieb. et Zucc) is a traditional Chinese medicine for the treatment of inflammation, hyperlipemia, favus, jaundice and scald. The extract of PCRR inhibits vascular endothelial growth factor (VEGF)-induced angiogenesis. The hypothesis is supported by analysis of PCRR extract and investigation of pharmacological role and signaling mechanism of PCRR extract in regulating angiogenic responses. The PCRR ethanolic extract was examined for its inhibitory effects on angiogenesis based on VEGF-treated human umbilical vein endothelial cells and in zebrafish model METHODS: The effects and signaling mechanism of a standardized ethanolic extract of PCRR were tested on cell proliferation, migration and tube formation in VEGF-treated human umbilical vein endothelial cells, and which was further validated in zebrafish embryo model. The treatment of PCRR extract in cultured endothelial cells inhibited VEGF-induced...

Research paper thumbnail of Clivorine, an otonecine pyrrolizidine alkaloid from Ligularia species, impairs neuronal differentiation via NGF-induced signaling pathway in cultured PC12 cells

Phytomedicine : international journal of phytotherapy and phytopharmacology, Jan 15, 2016

Pyrrolizidine alkaloids (PAs) are commonly found in many plants including those used in medical t... more Pyrrolizidine alkaloids (PAs) are commonly found in many plants including those used in medical therapeutics. The hepatotoxicities of PAs have been demonstrated both in vivo and in vitro; however, the neurotoxicities of PAs are rarely mentioned. In this study, we aimed to investigate in vitro neurotoxicities of clivorine, one of the PAs found in various Ligularia species, in cultured PC12 cells. PC12 cell line was employed to first elucidate the neurotoxicity and the underlying mechanism of clivorine, including cell viability and morphology change, neuronal differentiation marker and signaling pathway. PC12 cells were challenged with series concentrations of clivorine and/or nerve growth factor (NGF). The cell lysates were collected for MTT assay, trypan blue staining, immunocytofluorescent staining, qRT-PCR and western blotting. Clivorine inhibited cell proliferation and neuronal differentiation evidenced by MTT assay and dose-dependently reducing neurite outgrowth, respectively. I...

Research paper thumbnail of Andrographolide induces cell cycle arrest at G2/M phase and cell death in HepG2 cells via alteration of reactive oxygen species

European Journal of Pharmacology, 2007

The cytotoxicity of andrographolide to HepG2 human hepatoma cells was investigated in the present... more The cytotoxicity of andrographolide to HepG2 human hepatoma cells was investigated in the present study. Growth of HepG2 cells was affected in the presence of andrographolide with an IC 50 of 40.2 μM after 48 h treatment. Flow cytometric analysis and DNA fragmentation assay revealed that andrographolide induced cell cycle arrest at G2/M phase and a late apoptosis of the cells. The occurrence of cell cycle arrest was accompanied by the collapse of mitochondrial membrane potential (MMP) and an intracellular increase of hydrogen peroxide (H 2 O 2) but a decrease of superoxide radicals (O 2 U −) and reduced glutathione. In the treated cells, expression of Bax as well as the transcriptional controller of this pro-apoptotic gene, p53, was upregulated but not other apoptotic proteins such as Bad, Bcl-2 and Bcl-X L. Although the activity of caspase-3, which has direct effect on apoptosis, was also enhanced by the presence of andrographolide, cell death of HepG2 could neither be prevented by a specific inhibitor of capsase-3 nor the pan-caspase inhibitor-zVAD (Val-Ala-Asp), indicating that it was a caspase-independent cell death. Since the overall percentage of apoptotic cells was relatively small throughout the experimental studies, we conclude that the cytotoxic effect of andrographolide on HepG2 cells is primary attributed to the induction of cell cycle arrest via the alteration of cellular redox status.

Research paper thumbnail of Origin of Red Color in Edible Bird’s Nests Directed by the Binding of Fe Ions to Acidic Mammalian Chitinase-like Protein

Journal of Agricultural and Food Chemistry, 2018

The red color of Edible bird's nest (EBN) remains a mystery over hundreds of years. Here, differe... more The red color of Edible bird's nest (EBN) remains a mystery over hundreds of years. Here, different analytical methods were employed to identify the color origin of EBN. The treatment of White EBN with NaNO 2 /HCl turned that into red color. In simulated gastric fluid (SGF)-digested EBN, the HPLC chromatogram, NMR spectrum, circular dichroism spectrum and Raman spectrum of a NaNO 2-treated White EBN closely resembled with that of authentic Red EBN. From the HPLC chromatogram of SGF-digested EBN, the peptides associated with red color were identified in Red EBN and NaNO 2-treated White EBN. Several lines of evidence indicated that the color-containing peptide could be derived from acidic mammalian chitinase-like (AMCase-like) protein of EBN. Besides, there was a noticeable increase in Fe-O bonding intensity after the color change. Based on the findings, we proposed the oxidation of Fe ion in AMCase-like protein contributed significantly to the color change of EBN.

Research paper thumbnail of Editorial: Edible Bird’s Nest—Chemical Composition and Potential Health Efficacy and Risks

Frontiers in Pharmacology, 2021

Edible bird’s nest (EBN) is a popular delicacy in the Asian Pacific region: this is a salivary se... more Edible bird’s nest (EBN) is a popular delicacy in the Asian Pacific region: this is a salivary secretion from several Aerodramus spp. swiftlets, mainlyAerodramus fuciphagus, which originated in Southeast Asian countries, including Indonesia, Malaysia, Thailand, and Vietnam. The historical record of EBN for human consumption can be tracked back to about 1,500 years ago in China. Today, the consumption of EBN as food or as a medicinal product is very common in Asian populations. According to ancient literature, EBN is able to alleviate respiratory health conditions, such as asthma, and is believed to have an impact in skin physiology. Despite the potential functional roles and popularity of this ethnomedicine in Asian cultures, the pharmacological research on EBN is still very limited. These claims of beneficial effects are questionable due to the lack of strong supporting experimental evidence. On the other hand, the production of EBN today is totally depending on swiftlets. The natu...

Research paper thumbnail of MOESM1 of Indication of nerve growth factor binding components from herbal extracts by HerboChip: a platform for drug screening on a chip

Additional file 1. Nerve growth factor (NGF) induces the differentiation of PC12 cells. (A): Imag... more Additional file 1. Nerve growth factor (NGF) induces the differentiation of PC12 cells. (A): Image of PC12 cells treated with 50 ng/mL of NGF for 48 hours. Bar = 10 Îźm. (B): PC12 cells were serum-starved for 3 hours and then treated with 0.5 to 50ng/mL of NGF for 48 hours. The cell lysates (20 Îźg) were subjected to western blot for NF68 (~68 kDa), NF200 (~200 kDa) and GAPDH (~38 kDa). GAPDH served as a loading control, n = 4.

Research paper thumbnail of MOESM1 of Authentication of Acori Tatarinowii Rhizoma (Shi Chang Pu) and its adulterants by morphological distinction, chemical composition and ITS sequencing

Additional file 1. Sequence alignment of the ITS regions and 5.8S rRNA genes from A. tatarinowii,... more Additional file 1. Sequence alignment of the ITS regions and 5.8S rRNA genes from A. tatarinowii, A. gramineus, A. calamus and A. altaica. The coding regions are boxed. Primer sequences used for amplification are indicated by arrows. Identical sequences are indicated by (*). Gaps (-) are introduced for the best alignment.

Research paper thumbnail of A comprehensive proteomics study on edible bird’s nest using new monoclonal antibody approach and application in quality control

Journal of Food Composition and Analysis, 2018

Edible bird's nest (EBN) is a glue-like substance deriving from salivary secretion by specific sw... more Edible bird's nest (EBN) is a glue-like substance deriving from salivary secretion by specific swiftlets, and protein is considered as the main component of EBN. Accounting over 50% by weight, the exact identities of EBN proteins are still not well understood, due to difficulties of extraction, purification and identification. By using EBN proteins as antigens, 31 monoclonal antibodies specifically against the proteins were generated. The proteins of EBN were subjected to identification by shotgun proteomics. Six protein identities were revealed, including acidic mammalian chitinase (AMCase)-like, mucin 5AC-like and ovoinhibitor-like proteins. In parallel, the monoclonal antibodies were used to immunoprecipitate proteins from EBN extract, and subsequently the precipitated product(s) was identified. AMCase-like protein was most frequently precipitated by the antibodies. The existence of AMCase-like protein in EBN was further verified by: (i) recognition of chicken AMCase by our anti-EBN antibodies; and (ii) recognition of EBN AMCase-like protein by a commercial anti-AMCase antibody. The antibody was highly sensitive and selective to AMCase-like protein in EBN products, with limit of detection at 0.01 μg/mL in ELISA test. Thus, AMCase-like protein, or its antibody, could be used as a new quality control marker for EBN.

Research paper thumbnail of Complete digestion of edible bird's nest releases free N-acetylneuraminic acid and small peptides: an efficient method to improve functional properties

Food & function, Jan 17, 2018

Edible bird's nest (EBN), an Asian health food, contains insoluble proteins and conjugated N-... more Edible bird's nest (EBN), an Asian health food, contains insoluble proteins and conjugated N-acetylneuraminic acid (NANA) that are difficult to be absorbed by humans. In order to increase the nutritional value of EBN, we developed methods to digest EBN targeting the release of proteins and NANA. By using simulated gastric fluid under acidic conditions, the complex proteins were fully digested into smaller peptides, and in parallel, NANA was fully released from the conjugated form. The completely digested EBN showed better nutraceutical properties. In a skin whitening test, the EBN digest showed stronger inhibition of melanogenesis of cultured B16 cells and enzymatic activity of tyrosinase, as compared to that of undigested EBN. In addition, the EBN digest exhibited stronger osteogenic activity in cultured osteoblasts. Thus, the complete digestion of EBN could be applied to the development of a new generation of EBN health food products, including EBN drinks and skincare products.

Research paper thumbnail of Binding of Resveratrol to Vascular Endothelial Growth Factor Suppresses Angiogenesis by Inhibiting the Receptor Signaling

Journal of Agricultural and Food Chemistry, 2018

Resveratrol is a polyphenol commonly found in plants and food health products, such as grape and ... more Resveratrol is a polyphenol commonly found in plants and food health products, such as grape and red wine, and was identified for its binding to vascular endothelial growth factor (VEGF) by using HerboChips screening. The binding, therefore, resulted in alterations of VEGF binding to its receptor and revealed the roles of VEGF in angiogenesis. Several lines of evidence gave support to the inhibitory activities of resveratrol in VEGF-triggered angiogenesis. In human umbilical vein endothelial cells (HUVECs), compared with a VEGF-induced group, resveratrol, at a high concentration, suppressed VEGF-mediated endothelial cell proliferation, cell migration, cell invasion, and tube formation by 80 ± 9.01%, 140 ± 3.78%, 110 ± 7.51%, and 120 ± 10.26%, respectively. Moreover, resveratrol inhibited the subintestinal vessel formation in zebrafish embryo. In signaling cascades, application of resveratrol in HUVECs reduced the VEGF-triggered VEGF receptor 2 phosphorylation and c-Jun N-terminal kinase phosphorylation. Moreover, the VEGF-mediated phosphorylations of endothelial nitric oxide synthase, protein kinase B, and extracellular signal-regulated kinase were obviously decreased by (3 ± 0.37)-, (2 ± 0.27)- and (6 ± 0.23)-fold, respectively, in the presence of resveratrol at high concentration. Parallelly, the VEGF-induced reactive oxygen species formation was significantly decreased by 50 ± 7.88% to 120 ± 14.82% under resveratrol treatment. Thus, our results provided support to the antiangiogenic roles of resveratrol, as well as its related signaling mechanisms, in attenuating the VEGF-mediated responses. The present results supported possible development of resveratrol, which should be considered as a therapeutic agent in terms of prevention and clinical treatment of diseases related to angiogenesis.

Research paper thumbnail of Quality Control on Herbal Medicine and Its Application

Evidence-Based Complementary and Alternative Medicine, 2018

Research paper thumbnail of Molecular studies of the vascular endothelial growth factor (Vegf-A) and VEGF-receptor (Flk-1) genes of grass carp

... by Chan Kar Lun Gallant April 2005 ... Apart from its adaptive role in hypoxia, VEGF is an im... more ... by Chan Kar Lun Gallant April 2005 ... Apart from its adaptive role in hypoxia, VEGF is an important angiogenic factor in various estrogen target tissues such as the placenta (Pepe and Albrecht, 1999), pituitary (Ochoa et al., 2000), testis (Rudolfsson et al., 2004), ovary and uterus ...

Research paper thumbnail of Molecular Interaction between Andrographolide and Glutathione Follows Second Order Kinetics

Chemical and Pharmaceutical Bulletin, 2008

The intracellular level of glutathione (GSH) was significantly decreased after the addition of an... more The intracellular level of glutathione (GSH) was significantly decreased after the addition of andrographolide (1) to cell cultures of HepG2. When the molecular interaction between andrographolide and GSH was investigated under a condition mimicking the in vivo environment, we observed that the level of GSH dropped in the presence of andrographolide. Stoichiometric analysis indicates that the reaction between these two reactants was 1 to 1 at pH 7 and followed second order kinetics. The activation energy of the overall reaction was 41.9؎10 kJ • mol ؊1 according to the Arrhenius equation. Using a micro-liquid-liquid extraction method followed by micellar electrokinetic chromatographic separation, two major products were isolated and identified, and their chemical structures were determined as 14-deoxy-12-(glutathione-amino)-andrographolide (2) and 14deoxy-12-(glutathione-S-yl)-andrographolide (3). Based on these structural findings, a hypothetical mechanism of reaction between glutathione and andrographolide was proposed. It is concluded that the a a,b b-unsaturated lactone moiety of andrographolide reacts with GSH through a Michael addition followed by dehydration of the adduct.

Research paper thumbnail of Searching for Active Ingredients in Edible Bird’s Nest

Journal of Complementary Medicine & Alternative Healthcare, 2018

Glycoprotein-A Longmystery on EBN Protein comprised the largest part of EBN, over half of the nes... more Glycoprotein-A Longmystery on EBN Protein comprised the largest part of EBN, over half of the nest made of protein. However, the proteomics study was hindered by several limitations. The heavily glycosylated chains of peptide polymer in EBN were very difficult to be hydrolyzed, and thus the rooms for enzymatic reactions were always limited. The first report of protein on EBN, published in 1975 by a French group, indicated that the protein of EBN was actually glycoprotein [14].

Research paper thumbnail of Redox regulation by andrographolide induced cell cycle arrest and cell death in HepG2 cells

Research paper thumbnail of An Optimized Extract, Named Self-Growth Colony, from Platelet-Rich Plasma Shows Robust Skin Rejuvenation and Anti-Ageing Properties: A Novel Technology in Development of Cosmetics

Skin Pharmacology and Physiology, 2021

Introduction: Inspired by application of platelet-rich plasma (PRP) in skin treatment during inju... more Introduction: Inspired by application of platelet-rich plasma (PRP) in skin treatment during injuries, an extracting method was developed here to recover high amounts of cytokines and growth factors from PRP; this prepared extract was named as self-growth colony (SGC). Methods: In optimization of SGC preparation, various parameters were tested, for example, centrifugation force, freeze-thaw, sonication, and inclusion of calcium chelator. The amounts of cytokines and growth factors, including platelet factor 4, β-thromboglobulin, epidermal growth factor, vascular endothelial growth factor, platelet-derived growth factor, were measured by ELISA assay. Results: By comparing to PRP, the prepared SGC contained a significant higher amount of measured growth factors. In addition, the degradation of growth factors within SGC during the storage was calibrated, which showed better stability as compared to that of PRP preparation. Having possible application in skin care, the optimized SGC was...

Research paper thumbnail of The binding of kaempferol-3-O-rutinoside to vascular endothelial growth factor potentiates anti-inflammatory efficiencies in lipopolysaccharide-treated mouse macrophage RAW264.7 cells

Phytomedicine, 2021

Reported cases encountered difficulty in differentiating between inflammatory carcinoma and breas... more Reported cases encountered difficulty in differentiating between inflammatory carcinoma and breast edema caused by congestive heart failure especially if the breast edema is unilateral. Our presented case is an elderly woman with unilateral breast edema due to congestive heart failure that was initially suspected to have breast cancer based on clinical findings. However imaging studies showed breast edema pattern with no definite underlying mass. This edema was resolved with standard treatment of heart failure. Congestive heart failure may be a possible cause of unilateral breast edema especially in a patient with background of congestive heart failure.

Research paper thumbnail of The anti-bacterial effects of aerial parts of Scutellaria baicalensis: Potential application as an additive in aquaculture feedings

Aquaculture, 2020

The root of Scutellaria baicalensis (Scutellaria Radix) is a medicinal part being used as a herba... more The root of Scutellaria baicalensis (Scutellaria Radix) is a medicinal part being used as a herbal drug; while its stem and leaf (aerial part) are considered as waste. Several reports have shown that aerial part of S. baicalensis (SBA) has chemical similarity with its root, suggesting the possible usage of this non-medicinal part. Thus, the usage of SBA as an additive in aquaculture feeding could be a new way to recycle the waste. The water extract of SBA inhibited the growth of several common pathogenic bacteria in aquaculture, e.g. Aeromonas hydrophila, Edwardsiella tarda, Vibrio alginolyticus and Vibrio harveyi. In cultured macrophage cells (RAW 264.7), application of SBA extract showed strong anti-inflammation effect, which inhibited the expression of inflammatory cytokine, i.e. IL-1β, as induced by LPS. Similarly, SBA extract suppressed the LPS-induced transcriptional activity mediated by NF-κB. When applied in fish aquaculture, the extract of SBA was mixed into the feedings of Siganus fuscescens (rabbit fish) that was cultured with a mixture of pathogenic bacteria. The expression levels of COX-2, IL-1β and TNF-α were markedly reduced in the present of SBA extract. Our investigations show the anti-bacterial effect of SBA extract, as well as its potential anti-inflammation effects both in vitro and in vivo, which therefore suggest the possible development of S. baicalensis aerial part in fish aquaculture.

Research paper thumbnail of Kaempferol, a Major Flavonoid in Ginkgo Folium, Potentiates Angiogenic Functions in Cultured Endothelial Cells by Binding to Vascular Endothelial Growth Factor

Frontiers in Pharmacology, 2020

Kaempferol is a major flavonoid in Ginkgo Folium and other edible plants, which is being proposed... more Kaempferol is a major flavonoid in Ginkgo Folium and other edible plants, which is being proposed here to have roles in angiogenesis. Angiogenesis is important in both physiological and pathological development. Here, kaempferol was shown to bind with vascular endothelial growth factor (VEGF), probably in the heparin binding domain of VEGF: this binding potentiated the angiogenic functions of VEGF in various culture models. Kaempferol potentiated the VEGF-induced cell motility in human umbilical vein endothelial cells (HUVECs), as well as the sub-intestinal vessel sprouting in zebrafish embryos and formation of microvascular in rat aortic ring. In cultured HUVECs, application of kaempferol strongly potentiated the VEGF-induced phosphorylations of VEGFR2, endothelial nitric oxide synthase (eNOS) and extracellular signal-regulated kinase (Erk) in time-dependent and concentration-dependent manners, and in parallel the VEGFmediated expressions of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were significantly enhanced. In addition, the potentiation effect of kaempferol was revealed in VEGF-induced migration of skin cell and monocyte. Taken together, our results suggested the pharmacological roles of kaempferol in potentiating VEGF-mediated functions should be considered.

Research paper thumbnail of Isoorientin derived from Gentiana veitchiorum Hemsl. flowers inhibits melanogenesis by down-regulating MITF-induced tyrosinase expression

Phytomedicine, 2018

Background: Gentiana is a genus of flowering plants in Gentianaceae family, which comprises of 1,... more Background: Gentiana is a genus of flowering plants in Gentianaceae family, which comprises of 1,600 species. The roots of few species of Gentiana, also known as Long Dan Cao in Chinese, are traditionally used in herbal remedies for a wide variety of liver-associated diseases. The medicinal part of Gentiana is root; however, the trumpet-shaped flowers are seldom being used. Purpose: We investigated the anti-melanogenesis effect of water extract of Gentiana veitchiorum Hemsl. flowers, and isoorientin was identified to be the active compound. Study design: We tested the anti-melanogenesis effects of extracts deriving from different parts of G. veitchiorum, followed by identification of active ingredients within the extracts. The mechanism of inhibitory effect on melanogenesis, triggered by isoorientin, was elucidated by in vitro analyses. Methods: HPLC was applied to identify the components in water extracts from different parts of G. veitchiorum. The cytotoxicity of extracts and pure compounds in cultured B16F10 murine melanoma cells was determined by MTT and trypan blue assays. Melanin assay, tyrosinase assay, RT-PCR, luciferase assay and western blot were used to analyze the effect of isoorientin in melanin content, tyrosinase activity, as well as the expressions of those related genes and proteins. Results: We identified an inhibitory effect on melanogenesis from water extract of G. veitchiorum flowers in B16F10 cells. Isoorientin, a major flavone in the extract, was identified to be an active ingredient causing reduction in melanin content in a dose-dependent manner. Such reduction was suggested to be a result of suppressed expression of tyrosinase (TYR), tyrosinase related protein-1 (TRP1) and DOPA-chrome tautomerase (DCT). Isoorientin also suppressed the expression of microphthalmia-associated transcription factor (MITF) through the phosphorylation of cAMP response element-binding protein (CREB). Conclusion: These findings indicate that isoorientin derived from G. veitchiorum flowers may be a potential skin lightening agent for the treatment of skin pigmentary disorders. monophosphate (cAMP)-mediated microphthalmia-associated transcription factor (MITF). MITF is a basic helix-loop-helix leucine zipper transcription factor playing a key role in melanocyte differentiation, and which is also a master activator in triggering the expression of various melanin synthesizing enzymes through binding to E-box sequence (Busca and Ballotti, 2000; Hartman and Czyz, 2014). Melanin synthesis is a multi-step process in which tyrosinase is a key enzyme as

Research paper thumbnail of The extract of Polygoni Cuspidati Rhizoma et Radix suppresses the vascular endothelial growth factor-induced angiogenesis

Phytomedicine : international journal of phytotherapy and phytopharmacology, Jan 15, 2018

Polygoni Cuspidati Rhizoma et Radix (PCRR; the root and rhizome of Polygonum cuspidatum Sieb. et ... more Polygoni Cuspidati Rhizoma et Radix (PCRR; the root and rhizome of Polygonum cuspidatum Sieb. et Zucc) is a traditional Chinese medicine for the treatment of inflammation, hyperlipemia, favus, jaundice and scald. The extract of PCRR inhibits vascular endothelial growth factor (VEGF)-induced angiogenesis. The hypothesis is supported by analysis of PCRR extract and investigation of pharmacological role and signaling mechanism of PCRR extract in regulating angiogenic responses. The PCRR ethanolic extract was examined for its inhibitory effects on angiogenesis based on VEGF-treated human umbilical vein endothelial cells and in zebrafish model METHODS: The effects and signaling mechanism of a standardized ethanolic extract of PCRR were tested on cell proliferation, migration and tube formation in VEGF-treated human umbilical vein endothelial cells, and which was further validated in zebrafish embryo model. The treatment of PCRR extract in cultured endothelial cells inhibited VEGF-induced...

Research paper thumbnail of Clivorine, an otonecine pyrrolizidine alkaloid from Ligularia species, impairs neuronal differentiation via NGF-induced signaling pathway in cultured PC12 cells

Phytomedicine : international journal of phytotherapy and phytopharmacology, Jan 15, 2016

Pyrrolizidine alkaloids (PAs) are commonly found in many plants including those used in medical t... more Pyrrolizidine alkaloids (PAs) are commonly found in many plants including those used in medical therapeutics. The hepatotoxicities of PAs have been demonstrated both in vivo and in vitro; however, the neurotoxicities of PAs are rarely mentioned. In this study, we aimed to investigate in vitro neurotoxicities of clivorine, one of the PAs found in various Ligularia species, in cultured PC12 cells. PC12 cell line was employed to first elucidate the neurotoxicity and the underlying mechanism of clivorine, including cell viability and morphology change, neuronal differentiation marker and signaling pathway. PC12 cells were challenged with series concentrations of clivorine and/or nerve growth factor (NGF). The cell lysates were collected for MTT assay, trypan blue staining, immunocytofluorescent staining, qRT-PCR and western blotting. Clivorine inhibited cell proliferation and neuronal differentiation evidenced by MTT assay and dose-dependently reducing neurite outgrowth, respectively. I...

Research paper thumbnail of Andrographolide induces cell cycle arrest at G2/M phase and cell death in HepG2 cells via alteration of reactive oxygen species

European Journal of Pharmacology, 2007

The cytotoxicity of andrographolide to HepG2 human hepatoma cells was investigated in the present... more The cytotoxicity of andrographolide to HepG2 human hepatoma cells was investigated in the present study. Growth of HepG2 cells was affected in the presence of andrographolide with an IC 50 of 40.2 μM after 48 h treatment. Flow cytometric analysis and DNA fragmentation assay revealed that andrographolide induced cell cycle arrest at G2/M phase and a late apoptosis of the cells. The occurrence of cell cycle arrest was accompanied by the collapse of mitochondrial membrane potential (MMP) and an intracellular increase of hydrogen peroxide (H 2 O 2) but a decrease of superoxide radicals (O 2 U −) and reduced glutathione. In the treated cells, expression of Bax as well as the transcriptional controller of this pro-apoptotic gene, p53, was upregulated but not other apoptotic proteins such as Bad, Bcl-2 and Bcl-X L. Although the activity of caspase-3, which has direct effect on apoptosis, was also enhanced by the presence of andrographolide, cell death of HepG2 could neither be prevented by a specific inhibitor of capsase-3 nor the pan-caspase inhibitor-zVAD (Val-Ala-Asp), indicating that it was a caspase-independent cell death. Since the overall percentage of apoptotic cells was relatively small throughout the experimental studies, we conclude that the cytotoxic effect of andrographolide on HepG2 cells is primary attributed to the induction of cell cycle arrest via the alteration of cellular redox status.

Research paper thumbnail of Origin of Red Color in Edible Bird’s Nests Directed by the Binding of Fe Ions to Acidic Mammalian Chitinase-like Protein

Journal of Agricultural and Food Chemistry, 2018

The red color of Edible bird's nest (EBN) remains a mystery over hundreds of years. Here, differe... more The red color of Edible bird's nest (EBN) remains a mystery over hundreds of years. Here, different analytical methods were employed to identify the color origin of EBN. The treatment of White EBN with NaNO 2 /HCl turned that into red color. In simulated gastric fluid (SGF)-digested EBN, the HPLC chromatogram, NMR spectrum, circular dichroism spectrum and Raman spectrum of a NaNO 2-treated White EBN closely resembled with that of authentic Red EBN. From the HPLC chromatogram of SGF-digested EBN, the peptides associated with red color were identified in Red EBN and NaNO 2-treated White EBN. Several lines of evidence indicated that the color-containing peptide could be derived from acidic mammalian chitinase-like (AMCase-like) protein of EBN. Besides, there was a noticeable increase in Fe-O bonding intensity after the color change. Based on the findings, we proposed the oxidation of Fe ion in AMCase-like protein contributed significantly to the color change of EBN.

Research paper thumbnail of Editorial: Edible Bird’s Nest—Chemical Composition and Potential Health Efficacy and Risks

Frontiers in Pharmacology, 2021

Edible bird’s nest (EBN) is a popular delicacy in the Asian Pacific region: this is a salivary se... more Edible bird’s nest (EBN) is a popular delicacy in the Asian Pacific region: this is a salivary secretion from several Aerodramus spp. swiftlets, mainlyAerodramus fuciphagus, which originated in Southeast Asian countries, including Indonesia, Malaysia, Thailand, and Vietnam. The historical record of EBN for human consumption can be tracked back to about 1,500 years ago in China. Today, the consumption of EBN as food or as a medicinal product is very common in Asian populations. According to ancient literature, EBN is able to alleviate respiratory health conditions, such as asthma, and is believed to have an impact in skin physiology. Despite the potential functional roles and popularity of this ethnomedicine in Asian cultures, the pharmacological research on EBN is still very limited. These claims of beneficial effects are questionable due to the lack of strong supporting experimental evidence. On the other hand, the production of EBN today is totally depending on swiftlets. The natu...

Research paper thumbnail of MOESM1 of Indication of nerve growth factor binding components from herbal extracts by HerboChip: a platform for drug screening on a chip

Additional file 1. Nerve growth factor (NGF) induces the differentiation of PC12 cells. (A): Imag... more Additional file 1. Nerve growth factor (NGF) induces the differentiation of PC12 cells. (A): Image of PC12 cells treated with 50 ng/mL of NGF for 48 hours. Bar = 10 Îźm. (B): PC12 cells were serum-starved for 3 hours and then treated with 0.5 to 50ng/mL of NGF for 48 hours. The cell lysates (20 Îźg) were subjected to western blot for NF68 (~68 kDa), NF200 (~200 kDa) and GAPDH (~38 kDa). GAPDH served as a loading control, n = 4.

Research paper thumbnail of MOESM1 of Authentication of Acori Tatarinowii Rhizoma (Shi Chang Pu) and its adulterants by morphological distinction, chemical composition and ITS sequencing

Additional file 1. Sequence alignment of the ITS regions and 5.8S rRNA genes from A. tatarinowii,... more Additional file 1. Sequence alignment of the ITS regions and 5.8S rRNA genes from A. tatarinowii, A. gramineus, A. calamus and A. altaica. The coding regions are boxed. Primer sequences used for amplification are indicated by arrows. Identical sequences are indicated by (*). Gaps (-) are introduced for the best alignment.

Research paper thumbnail of A comprehensive proteomics study on edible bird’s nest using new monoclonal antibody approach and application in quality control

Journal of Food Composition and Analysis, 2018

Edible bird's nest (EBN) is a glue-like substance deriving from salivary secretion by specific sw... more Edible bird's nest (EBN) is a glue-like substance deriving from salivary secretion by specific swiftlets, and protein is considered as the main component of EBN. Accounting over 50% by weight, the exact identities of EBN proteins are still not well understood, due to difficulties of extraction, purification and identification. By using EBN proteins as antigens, 31 monoclonal antibodies specifically against the proteins were generated. The proteins of EBN were subjected to identification by shotgun proteomics. Six protein identities were revealed, including acidic mammalian chitinase (AMCase)-like, mucin 5AC-like and ovoinhibitor-like proteins. In parallel, the monoclonal antibodies were used to immunoprecipitate proteins from EBN extract, and subsequently the precipitated product(s) was identified. AMCase-like protein was most frequently precipitated by the antibodies. The existence of AMCase-like protein in EBN was further verified by: (i) recognition of chicken AMCase by our anti-EBN antibodies; and (ii) recognition of EBN AMCase-like protein by a commercial anti-AMCase antibody. The antibody was highly sensitive and selective to AMCase-like protein in EBN products, with limit of detection at 0.01 μg/mL in ELISA test. Thus, AMCase-like protein, or its antibody, could be used as a new quality control marker for EBN.

Research paper thumbnail of Complete digestion of edible bird's nest releases free N-acetylneuraminic acid and small peptides: an efficient method to improve functional properties

Food & function, Jan 17, 2018

Edible bird's nest (EBN), an Asian health food, contains insoluble proteins and conjugated N-... more Edible bird's nest (EBN), an Asian health food, contains insoluble proteins and conjugated N-acetylneuraminic acid (NANA) that are difficult to be absorbed by humans. In order to increase the nutritional value of EBN, we developed methods to digest EBN targeting the release of proteins and NANA. By using simulated gastric fluid under acidic conditions, the complex proteins were fully digested into smaller peptides, and in parallel, NANA was fully released from the conjugated form. The completely digested EBN showed better nutraceutical properties. In a skin whitening test, the EBN digest showed stronger inhibition of melanogenesis of cultured B16 cells and enzymatic activity of tyrosinase, as compared to that of undigested EBN. In addition, the EBN digest exhibited stronger osteogenic activity in cultured osteoblasts. Thus, the complete digestion of EBN could be applied to the development of a new generation of EBN health food products, including EBN drinks and skincare products.

Research paper thumbnail of Binding of Resveratrol to Vascular Endothelial Growth Factor Suppresses Angiogenesis by Inhibiting the Receptor Signaling

Journal of Agricultural and Food Chemistry, 2018

Resveratrol is a polyphenol commonly found in plants and food health products, such as grape and ... more Resveratrol is a polyphenol commonly found in plants and food health products, such as grape and red wine, and was identified for its binding to vascular endothelial growth factor (VEGF) by using HerboChips screening. The binding, therefore, resulted in alterations of VEGF binding to its receptor and revealed the roles of VEGF in angiogenesis. Several lines of evidence gave support to the inhibitory activities of resveratrol in VEGF-triggered angiogenesis. In human umbilical vein endothelial cells (HUVECs), compared with a VEGF-induced group, resveratrol, at a high concentration, suppressed VEGF-mediated endothelial cell proliferation, cell migration, cell invasion, and tube formation by 80 ± 9.01%, 140 ± 3.78%, 110 ± 7.51%, and 120 ± 10.26%, respectively. Moreover, resveratrol inhibited the subintestinal vessel formation in zebrafish embryo. In signaling cascades, application of resveratrol in HUVECs reduced the VEGF-triggered VEGF receptor 2 phosphorylation and c-Jun N-terminal kinase phosphorylation. Moreover, the VEGF-mediated phosphorylations of endothelial nitric oxide synthase, protein kinase B, and extracellular signal-regulated kinase were obviously decreased by (3 ± 0.37)-, (2 ± 0.27)- and (6 ± 0.23)-fold, respectively, in the presence of resveratrol at high concentration. Parallelly, the VEGF-induced reactive oxygen species formation was significantly decreased by 50 ± 7.88% to 120 ± 14.82% under resveratrol treatment. Thus, our results provided support to the antiangiogenic roles of resveratrol, as well as its related signaling mechanisms, in attenuating the VEGF-mediated responses. The present results supported possible development of resveratrol, which should be considered as a therapeutic agent in terms of prevention and clinical treatment of diseases related to angiogenesis.