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Biomolecules ; 9(8)2019 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-31405030


α-lipoic acid (ALA, thioctic acid) is an organosulfur component produced from plants, animals, and humans. It has various properties, among them great antioxidant potential and is widely used as a racemic drug for diabetic polyneuropathy-associated pain and paresthesia. Naturally, ALA is located in mitochondria, where it is used as a cofactor for pyruvate dehydrogenase (PDH) and α-ketoglutarate dehydrogenase complexes. Despite its various potentials, ALA therapeutic efficacy is relatively low due to its pharmacokinetic profile. Data suggests that ALA has a short half-life and bioavailability (about 30%) triggered by its hepatic degradation, reduced solubility as well as instability in the stomach. However, the use of various innovative formulations has greatly improved ALA bioavailability. The R enantiomer of ALA shows better pharmacokinetic parameters, including increased bioavailability as compared to its S enantiomer. Indeed, the use of amphiphilic matrices has capability to improve ALA bioavailability and intestinal absorption. Also, ALA's liquid formulations are associated with greater plasma concentration and bioavailability as compared to its solidified dosage form. Thus, improved formulations can increase both ALA absorption and bioavailability, leading to a raise in therapeutic efficacy. Interestingly, ALA bioavailability will be dependent on age, while no difference has been found for gender. The present review aims to provide an updated on studies from preclinical to clinical trials assessing ALA's usages in diabetic patients with neuropathy, obesity, central nervous system-related diseases and abnormalities in pregnancy.

J Sci Food Agric ; 99(13): 6001-6010, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31225640


BACKGROUND: In this study, we aimed to evaluate the influence of different extraction procedures [decoction, homogenizer-assisted extraction (HAE), infusion, maceration, Soxhlet and ultrasound-assisted extraction (UAE)] on the chemical profiling and biological properties of methanol and water extracts of Pulicaria dysenterica (L.) Bernh. The chemical profiles of the extracts were evaluated by high-performance liquid chromatography coupled to electrospray ionization and time-of-flight mass spectrometry (HPLC-ESI-TOF-MS). The antioxidant properties and enzymes (lipase, α-amylase, α-glucosidase, tyrosinase and cholinesterases) inhibitory potential of the extracts were evaluated. RESULTS: The chemical profiles were dependent on the type of extraction methods as well as on the type of solvent. The methanolic extracts showed higher levels of total phenolic, flavonoid, and phenolic acid content, while the highest total flavonol content was observed in the HAE-water extract. Forty different compounds were identified from P. dysenterica. In relation to the potential in vitro anti-diabetic effects, the highest activity against the studied key enzymes was observed for the macerated extract (α-amylase: 0.58 ± 0.03 and α- glucosidase: 1.65 ± 0.03 mmol ACAE g-1 ). The HAE-methanol extract was the most potent inhibitor of cholisterases, whereas the highest activities against tyrosinase were observed for UAE-methanol extract, followed by macerated and Soxhlet. The inhibitory activity of the studied extracts against lipase were in the order: soxhlet > macerated> HAE-methanol > UAE-methanol. CONCLUSION: This study has established scientific baseline data on the therapeutic properties of P. dysentrica, thereby advocating the need for further investigations in an endeavour to develop novel pharmaceuticals from this plant. © 2019 Society of Chemical Industry.

Extratos Vegetais/química , Pulicaria/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Análise Multivariada , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química , alfa-Glucosidases/química
Med Res Rev ; 39(6): 2153-2171, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31006878


Antiplatelet drugs reduce the risks associated with atherothrombotic events and show various applications in diverse cardiovascular diseases including myocardial infarctions. Efficacy of the current antiplatelet medicines including aspirin, clopidogrel, prasugrel and ticagrelor, and the glycoprotein IIb/IIIa antagonists, are limited due to their increased risks of bleeding, and antiplatelet drug resistance. Hence, it is important to develop new effective antiplatelet drugs, with fewer side-effects. The vast repertoire of natural peptides can be explored towards this goal. Proteins and peptides derived from snake venoms and plants represent exciting candidates for the development of novel and potent antiplatelet agents. Consequently, this review discusses multiple peptides that have displayed antiplatelet aggregation activity in preclinical drug development stages. This review also describes the antiplatelet mechanisms of the peptides, emphasizing the signaling pathways intervened by them. Also, the hurdles encountered during the development of peptides into antiplatelet drugs have been listed. Finally, hitherto unexplored peptides with the potential to prevent platelet aggregation are explored.

Phytochem Anal ; 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30511497


INTRODUCTION: In the quest for new sources of biologically-active compounds, the chemical, and biological profiles of two Globularia species (G. trichosantha Fisch. & C. A. Mey and G. orientalis L.) were investigated. METHODOLOGY: Chemical profiles were evaluated by high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS), as well as by their total phenolic, flavonoids, and phenolic acids contents. The antioxidant abilities of the investigated extracts were done using different assays including free radical scavenging [1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS)], reducing power (cupric reducing antioxidant capacity and ferric reducing antioxidant power), phosphomolybdenum, and metal chelating. Inhibitory potential against key enzymes involved in neurodegenerative diseases (cholinesterases; AChE, and BChE), diabetes (α-glucosidase and α-amylase), hyperpigmentation (tyrosinase) and obesity (pancreatic lipase) were evaluated. RESULTS: Globularia trichosantha and G. orientalis extracts showed remarkable antioxidant properties, with the water extracts being a better source of antioxidant compounds. Both species showed remarkable inhibitory effects against the target enzymes. However, for both species, only the acetyl acetate and methanolic extracts were potent against cholinesterases and lipase. CONCLUSION: HPLC-ESI-QTOF-MS analysis revealed the presence of 107 compounds from G. trichosantha and G. orientalis, among which, 43 compounds have been preliminarily characterised for the first time from the Globulariaceae family. To date, this study can be considered as the most comprehensive research focused on the characterisation of G. trichosantha and G. orientalis. Results amassed from this study tend to show that these plants represent a rich source of biologically active compounds which can be further explored and validated for their therapeutic potential.

J Biomol Struct Dyn ; : 1-13, 2018 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-30058457


Tragopogon dubius and Tussilago farfara are consumed as vegetables and used in folk medicine to manage common diseases. Herein, the chemical compositions and biological activities of different leaf extracts (ethyl acetate, methanol, and water) of T. dubius and T. farfara were evaluated. The antibacterial, antifungal, and antioxidant abilities of the extracts were tested using different assays including free radical scavenging, reducing power, phosphomolybdenum, and metal chelating assays. Enzyme inhibitory potentials were evaluated against cholinesterases, tyrosinase, α-amylase and α-glucosidase. Complexes of bioactive compounds (chlorogenic and rosmarinic acid) were docked into the enzymatic cavity of α-glucosidase and subjected to molecular dynamic calculation, enzyme conformational stability, and flexibility analysis. T. dubius and T. farfara extracts showed remarkable antioxidant potentials. Ethyl acetate extracts of T. dubius and T. farfara were the most potent inhibitors of acetylcholinesterase and butyrylcholinesterase. T. dubius ethyl acetate extract and T. farfara methanolic extract showed noteworthy activity against α-glucosidase. High performance liquid chromatography analysis revealed the abundance of some phenolic compounds including chlorogenic and rosmarinic acids. Ethyl acetate extract of T. dubius showed notable antifungal activity against all strains. Docking studies showed best pose for chlorogenic acid was stabilized by a network of hydrogen bonds with residues Asp1157, Asp1279, whereas rosmarinic acid showed several hydrogen bonds with Asp1157, Asp1420, Asp1526, Lys1460 and Trp1369. This study further validates the use of T. dubius and T. farfara in traditional medicine, as well as act as a stimulus for further studies for future biomedicine development. Communicated by Ramaswamy H. Sarma.

Fundam Clin Pharmacol ; 32(4): 400-413, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29505673


The ethyl acetate, methanolic, and water extracts of Fibigia eriocarpa were assessed for a panoply of bioactivities. Total phenolic and flavonoid content were quantified as well as individual phenolic compounds by HPLC-DAD. The in vitro antioxidant and enzyme (acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, α-amylase, and α-glucosidase) inhibitory potential of the extracts were evaluated. In silico molecular docking was used to investigate possible interaction between dominant compounds and selected enzymes. Vanillin (303 µg/g extract), apigenin (270 µg/g extract), and kaempferol (180 µg/g extract) were the main compounds in the ethyl acetate extract, while the methanolic extract was characterized by the presence of vanillin, rutin, and apigenin (616, 616 and 252 µg/g extract, respectively). (+)-catechin (1422 µg/g extract) was the main compound in the water extracts. The ethyl acetate extract was found to be a superior source of antioxidant compounds and enzyme inhibitors against above-mentioned enzymes. Docking studies revealed that p-hydroxybenzoic and (+)-catechin have the best scores for tyrosinase, while kaempferol and apigenin showed the best binding pose for α-glucosidase, AChE, and BChE. Results amassed herein are the first report on the phytochemical and biological attributes of F. eriocarpa, which tend to validate the pharmacological uses of this plant as an alternative medicine.

Brassicaceae/química , Extratos Vegetais/farmacologia , Acetatos/química , Antioxidantes/química , Antioxidantes/farmacologia , Apigenina/química , Apigenina/farmacologia , Catequina/química , Catequina/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Hidroxibenzoatos/química , Hidroxibenzoatos/farmacologia , Quempferóis/química , Quempferóis/farmacologia , Simulação de Acoplamento Molecular/métodos , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/farmacologia , Fenóis/química , Fenóis/farmacologia