Venom Proteome of Spine-Bellied Sea Snake (Hydrophis curtus) from Penang, Malaysia: Toxicity Correlation, Immunoprofiling and Cross-Neutralization by Sea Snake Antivenom

The venom proteome of Hydrophis curtus (synonym: Lapemis hardwickii) from Penang, Malaysia was investigated with nano-electrospray ionization-liquid chromatography tandem mass spectrometry (ESI-LCMS/MS) of the reverse-phase high-performance liquid chromatography (HPLC) venom fractions. Thirty distinct protein forms were identified as toxins from ten families. The three major protein families were phospholipase A2 (PLA2, 62.0% of total venom proteins), three-finger toxin (3FTX, 26.33%) and cysteine-rich secretory protein (CRiSP, 9.00%). PLA2 comprises diverse homologues (11 forms), predominantly the acidic subtypes (48.26%). 3FTX composed of one short alpha-neurotoxin (SNTX, 22.89%) and four long alpha-neurotoxins (LNTX, 3.44%). Both SNTX and LNTX were lethal in mice (intravenous LD50 = 0.10 and 0.24 μg/g, respectively) but the PLA2 were non-lethal (LD50 >1 μg/g). The more abundant and toxic SNTX appeared to be the main driver of venom lethality (holovenom LD50 = 0.20 μg/g). The heterologous Sea Snake Antivenom (SSAV, Australia) effectively cross-neutralized the venom (normalized potency = 9.35 mg venom neutralized per g antivenom) and the two neurotoxins in vivo, with the LNTX being neutralized more effectively (normalized potency = 3.5 mg toxin/g antivenom) than SNTX (normalized potency = 1.57 mg/g). SSAV immunorecognition was strong toward PLA2 but moderate-to-weak toward the alpha-neurotoxins, indicating that neutralization of the alpha-neurotoxins should be further improved.

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Integrated UPLC-MS/MS and UHPLC-Q-Orbitrap HRMS Analysis to Reveal Pharmacokinetics and Metabolism of Five Terpenoids from Alpiniae Oxyphyllae Fructus in rats

Current Drug Metabolism ◽

10.2174/1389200221666201217154219 ◽

2020 ◽

Vol 21 ◽

Author(s):

Lihua Zuo ◽

Jia Li ◽

Lianping Xue ◽

Qingquan Jia ◽

Zhuolun Li ◽

...

Keyword(s):

Mass Spectrometry ◽

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

High Performance ◽

Pharmacological Study ◽

Pharmacokinetic Analysis ◽

Validation Parameters ◽

Liquid Chromatography Tandem Mass ◽

Q Exactive

Background: Alpiniae oxyphyllae Fructus (AOF), as a traditional Chinese medicine (TCM), is widely used in the treatment of urinary, gastrointestinal and neurologic diseases in China. Although terpenoids are the main active ingredients of AOF, there are few researches on their pharmacokinetics and metabolism. Methods: In this study, a sensitive, rapid, accurate and novel ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established to evaluate the pharmacokinetic behavior of five terpenoids (oxyphyllenodiol B, (4S*,5E,10R*)-7-oxo-tri-nor-eudesm-5-en-4β-ol, 7-epi-teucrenone, (+)-(4R,5S,7R)-13- hydroxynootkatone, (E)-labda-12,14-dien-15(16)-olide-17-oic acid) in rats after oral administration of AOF extracts. And 27 metabolic metabolites of the five terpenoids were identified by ultra high performance liquid chromatography -Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry (UHPLC-Q-Orbitrap HRMS) based on precise mass and fragment ions. Results: The established pharmacokinetic analysis method showed good linearity over a wide concentration range, and the lower quantitative limit (LLOQ) were ranged from 0.97 to 4.25 ng/mL. And other validation parameters were within the acceptable range. In addition, 27 metabolites were identified in plasma, urine and feces samples, and the metabolic pathways of five terpenoids were mainly focus on glucoside conjugation, dehydration, desaturation and glycine conjugation. Conclusion: This is the first study on the pharmacokinetics and metabolism of five terpenoids in AOF at the same time, illuminating the disposal process of terpenoids in vivo. It was expected that the results of this study would provide some references for the apprehension of the action mechanism and the further pharmacological study of five terpenoids in AOF.

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Implication of Opioid Receptors in the Antihypertensive Effect of a Novel Chicken Foot-Derived Peptide

Biomolecules ◽

10.3390/biom10070992 ◽

2020 ◽

Vol 10 (7) ◽

pp. 992

Author(s):

Anna Mas-Capdevila ◽

Lisard Iglesias-Carres ◽

Anna Arola-Arnal ◽

Gerard Aragonès ◽

Begoña Muguerza ◽

...

Keyword(s):

Mass Spectrometry ◽

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Opioid Receptors ◽

High Performance ◽

Antihypertensive Effect ◽

High Resolution Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

The peptide AVFQHNCQE demonstrated to produce nitric oxide-mediated antihypertensive effect. This study investigates the bioavailability and the opioid-like activity of this peptide after its oral administration. For this purpose, in silico and in vitro approaches were used to study the peptide susceptibility to GI digestion. In addition, AVFQHNCQE absorption was studied both in vitro by using Caco-2 cell monolayers and in vivo evaluating peptide presence in plasma from Wistar rats by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and by ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Both in vivo and in vitro experiments demonstrated that peptide AVFQHNCQE was not absorbed. Thus, the potential involvement of opioid receptors in the BP-lowering effect of AVFQHNCQE was studied in the presence of opioid receptors-antagonist Naloxone. No changes in blood pressure were recorded in rats administered Naloxone, demonstrating that AVFQHNCQE antihypertensive effect is mediated through its interaction with opioid receptors. AVFQHNCQE opioid-like activity would clarify the antihypertensive properties of AVFQHNCQE despite its lack of absorption.

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