scholarly journals In vitro and in vivo evidence of tyrosinase inhibitory activity of a synthesized(Z)‐5‐(3‐hydroxy‐4‐methoxybenzylidene)‐2‐thioxothiazolidin‐4‐one (5‐HMT)

2019 ◽  
Vol 28 (6) ◽  
pp. 734-737 ◽  
Author(s):  
EunJin Bang ◽  
Eun Kyeong Lee ◽  
Sang‐Gyun Noh ◽  
Hee Jin Jung ◽  
Kyoung Mi Moon ◽  
...  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Yu-Lin Dai ◽  
Di Yang ◽  
Lai-Hui Song ◽  
Hong-Mei Yang ◽  
Jiang-Bo Yu ◽  
...  

To find new anti-UV and whitening agents, 21 fractions isolated from three preparations of ginseng (white, red, and black ginseng) were screened, and their antioxidant effects on AAPH- or H2O2-induced damage were investigated. Furthermore, the protective effect against UV-mediated apoptosis and the tyrosinase inhibitory activity of the targeted fractions were evaluated in vitro and in a zebrafish model. Among all fractions, F10 from white ginseng was selected as having the strongest anti-UV and antimelanogenesis activities. This fraction exhibited excellent inhibitory effects on the pigmentation of zebrafish, which may be due to its potential tyrosinase inhibitory activity. Additionally, the chemical composition of F10 was evaluated by UPLC-MS and NMR instruments. The results indicated that F10 had a carbohydrate content of more than 76%, and the weight-average molecular weight was approximately 239 Da. Disaccharide sucrose was the main active compound in F10. These results suggest that F10 could be used as an ingredient for whitening cosmetics and regarded as an anti-UV filter in the future.


1972 ◽  
Vol 28 (03) ◽  
pp. 351-358
Author(s):  
A.J Baillie ◽  
A. K Sim

SummaryThe activity of several synthetic compounds, rated from good to poor (or inactive) fibrinolytic activators, has been assessed by two different commonly-used in vitro methods. Compounds shown to be active over a narrow concentration range in the hanging clot test were shown to be inhibitors of plasmin and trypsin in the casein-olytic test. The inhibitory activity of these compounds was shown to increase with increasing substrate concentration and apparent activity in the hanging clot test. Possible explanations and relevance of these observations are discussed.


2003 ◽  
Vol 71 (11) ◽  
pp. 6648-6652 ◽  
Author(s):  
Steven Giles ◽  
Charles Czuprynski

ABSTRACT In this study we found that serum inhibitory activity against Blastomyces dermatitidis was principally mediated by albumin. This was confirmed in experiments using albumin from several mammalian species. Analbuminemic rat serum did not inhibit B. dermatitidis growth in vivo; however, the addition of albumin restored inhibitory activity. Inhibitory activity does not require albumin domain III and appears to involve binding of a low-molecular-weight yeast-derived growth factor.


2021 ◽  
Vol 16 (5) ◽  
pp. 1934578X2110166
Author(s):  
Xin Yi Lim ◽  
Janice Sue Wen Chan ◽  
Terence Yew Chin Tan ◽  
Bee Ping Teh ◽  
Mohd Ridzuan Mohd Abd Razak ◽  
...  

Drug repurposing is commonly employed in the search for potential therapeutic agents. Andrographis paniculata, a medicinal plant commonly used for symptomatic relief of the common cold, and its phytoconstituent andrographolide, have been repeatedly identified as potential antivirals against SARS-CoV-2. In light of new evidence emerging since the onset of the COVID-19 pandemic, this rapid review was conducted to identify and evaluate the current SARS-CoV-2 antiviral evidence for A. paniculata, andrographolide, and andrographolide analogs. A systematic search and screen strategy of electronic databases and gray literature was undertaken to identify relevant primary articles. One target-based in vitro study reported the 3CLpro inhibitory activity of andrographolide as being no better than disulfiram. Another Vero cell-based study reported potential SARS-CoV-2 inhibitory activity for both andrographolide and A. paniculata extract. Eleven in silico studies predicted the binding of andrographolide and its analogs to several key antiviral targets of SARS-CoV-2 including the spike protein-ACE-2 receptor complex, spike protein, ACE-2 receptor, RdRp, 3CLpro, PLpro, and N-protein RNA-binding domain. In conclusion, in silico and in vitro studies collectively suggest multi-pathway targeting SARS-CoV-2 antiviral properties of andrographolide and its analogs, but in vivo data are needed to support these predictions.


1990 ◽  
Vol 269 (3) ◽  
pp. 709-715 ◽  
Author(s):  
H Hayashi ◽  
M K Owada ◽  
S Sonobe ◽  
K Domae ◽  
T Yamanouchi ◽  
...  

Lipocortin I, a Ca2(+)-and phospholipid-binding protein without EF-hand structures, has many biological effects in vitro. Its actual role in vivo, however is unknown. We obtained and characterized five monoclonal antibodies to lipocortin I. Two of these monoclonal antibodies (L2 and L4-MAbs) reacted with the Ca(+)-bound form of lipocortin I, but not with the Ca2(+)-free form, both in vivo and in vitro. Lipocortin I required greater than or equal to 10 microM-Ca2+ to bind the two antibodies, and this Ca2+ requirement was not affected by phosphatidylserine. L2-MAb abolished the phospholipase A2 inhibitory activity of lipocortin I and inhibited its binding to Escherichia coli membranes and to phosphatidylserine in vitro. L4-MAb abolished the phospholipase A2 inhibitory activity of lipocortin I, but did not affect its binding to E. coli membranes or to phosphatidylserine. These findings indicated that the inhibition of phospholipase A2 by lipocortin I was not simply due to removal or capping of the substrates in E. coli membranes. Furthermore, an immunofluorescence study using L2-MAb showed the actual existence of Ca2(+)-bound form of lipocortin I in vivo.


2004 ◽  
Vol 134 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Fabiana Carvalho Morales ◽  
Daniel Rodrigues Furtado ◽  
Franklin David Rumjanek

2013 ◽  
Vol 49 (4) ◽  
pp. 803-809
Author(s):  
Monica Lacerda Lopes Martins ◽  
Henrique Poltronieri Pacheco ◽  
Iara Giuberti Perini ◽  
Dominik Lenz ◽  
Tadeu Uggere de Andrade ◽  
...  

In 1820, French naturalist August Saint Hillaire, during a visit in Espírito Santo (ES), a state in southeastern Brazil, reported a popular use of Cyperaceae species as antidote to snake bites. The plant may even have a hypotensive effect, though it was never properly researched. The in vitro inhibitory of the angiotensin converting enzyme (ACE) activity of eigth ethanolic extracts of Cyperaceae was evaluated by colorimetric assay. Total phenolic and flavonoids were determined using colorimetric assay. The hypotensive effect of the active specie (Rhychonospora exaltata, ERE) and the in vivo ACE assay was measured in vivo using male Wistar Kyoto (ERE, 0.01-100mg/kg), with acetylcholine (ACh) as positive control (5 µg/kg, i.v.). The evaluation of ACE in vivo inhibitory effect was performed comparing the mean arterial pressure before and after ERE (10 mg/kg) in animals which received injection of angiotensin I (ANG I; 0,03, 03 and 300 µg/kg, i.v.). Captopril (30 mg/kg) was used as positive control. Bulbostylis capillaris (86.89 ± 15.20%) and ERE (74.89 ± 11.95%, ERE) were considered active in the in vitro ACE inhibition assay, at 100 µg/mL concentration. ACh lead to a hypotensive effect before and after ERE's curve (-40±5% and -41±3%). ERE showed a dose-dependent hypotensive effect and a in vivo ACE inhibitory effect. Cyperaceae species showed an inhibitory activity of ACE, in vitro, as well as high content of total phenolic and flavonoids. ERE exhibited an inhibitory effect on both in vitro and in vivo ACE. The selection of species used in popular medicine as antidotes, along with the in vitro assay of ACE inhibition, might be a biomonitoring method for the screening of new medicinal plants with hypotensive properties.


2018 ◽  
Vol 1 (3) ◽  
pp. 106-110
Author(s):  
Novi Irwan Fauzi ◽  
Seno Aulia Ardiansyah ◽  
Saeful Hidayat

Daun malaka (Phyllanthus emblica L.) mempunyai potensi digunakan sebagai alternatif obat antidiabetes. Daun malaka menunjukkan efek hipoglikemia pada tikus yang diinduksi aloksan. Namun, mekanisme kerjanya belum diketahui pasti. Penelitian ini dilakukan dalam rangka skrining mekanisme kerja daun malaka sebagai antidiabetes. Skrining mekanisme kerja dilakukan terhadap fraksi air daun malaka melalui uji aktivitas inhibisi enzim α-glukosidase serta α-amilase secara in vitro dan pengujian aktivitas insulin-sensitizer terhadap ekstrak daun malaka dengan metode tes toleransi insulin secara in vivo. Fraksi air daun malaka menunjukkan aktivitas inhibisi terhadap enzim α-glukosidase serta α-amilase dengan nilai IC50 (Inhibitor Concentration 50) pada kedua enzim tersebut berturut-turut adalah 0,87% dan 8,64% b/v. Pada uji aktivitas insulin sensitizer, pemberian ekstrak daun malaka dapat meningkatkan sensitivitas insulin pada tikus diabet dengan kondisi resistensi insulin. Nilai KTTI pada kelompok tikus diabet yang diberi ekstrak daun malaka dosis 100 dan 500 mg/kgbb tikus (74,89 dan 75,57) lebih tinggi dibandingkan kelompok tikus diabet (38,41) dan kadar glukosa darah yang lebih rendah selama interval waktu pengukuran. Daun malaka telah diketahui mampu meningkatkan sekresi insulin dan pada penelitian ini menunjukkan aktivitas inhibisi enzim α-glukosidase serta α-amilase secara in vitro dan menunjukkan aktivitas insulinsensitizer pada tikus diabet dengan kondisi resistensi insulin.   Malaka leaf (Phyllanthus emblica L.) has the potential to be used as an alternative antidiabetic drug. Malacca leaves showed hypoglycemia effect in rat induced by alloxan. However, the mechanism of action is not yet known. This study was conducted to evaluate the mechanism of action of Malaka leaves as antidiabetic. Screening of the mechanism of action was carried out on the water fraction of Malaka leaf  byinhibitory activity examination  on α-glucosidase and α-amylase by in vitro studyand Evaluation of insulin-sensitizer activity of Maaka leaf leaf extract was conducted by invivo  insulin tolerance test method. Malaka leaf water fraction showed inhibitory activity against the α-glucosidase and α-amylase with IC50 values ​​(Inhibitory Concentration 50)  of0.87% and 8.64% b / v on both enzyme, respectively. The evaluation of insulin sensitizer revelead that administration ofMalaka  leaf extract can increase insulin sensitivity in diabetic rat with insulin resistance.KTTI values ​​in diabetic rats given malaka extract  at the dose of 100 and 500 mg / kg BW (74.89 and 75.57) were higher than diabetics rat (38.41) and the extract also decrease blood glucose levels during measurement time intervals . Malaka leafhas been known to increase insulin secretion and the study showedthe  inhibitory activity on α-glucosidase and α-amylase by in vitro study and showed insulinsensitizer activity in diabetic rat with insulin resistance.


Fitoterapia ◽  
2016 ◽  
Vol 110 ◽  
pp. 142-149 ◽  
Author(s):  
Heng-Wen Chen ◽  
Xuan-Hui He ◽  
Rong Yuan ◽  
Ben-Jun Wei ◽  
Zhong Chen ◽  
...  

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