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Effects of Medium Molecular Weight Heparinyl Phenylalanine on Type I Hypersensitivity

Seiichi Takeda1, Takao Toda2, Kazuki Nakamura3

  • 1Research and Development Center, Fuso Pharmaceutical Industries Ltd, Osaka, Japan sei-takeda@fuso-pharm.co.jp.

In Vivo (Athens, Greece)
|December 28, 2018
PubMed
Abstract

Insights

Medium molecular weight heparinyl phenylalanine (MHF) effectively inhibits type I hypersensitivity reactions by reducing histamine release. This compound shows potential as a potent anti-allergic agent, unlike MHR.

Area of Science:

  • Immunology
  • Pharmacology
  • Allergy Research

Background:

  • Heparin (HE) derivatives were synthesized to mitigate side effects associated with anticoagulant action.
  • Medium molecular weight heparinyl phenylalanine (MHF) and medium molecular weight heparinyl arginine (MHR) were developed from heparin.

Purpose of the Study:

  • To investigate the inhibitory effects of MHF and MHR on type I hypersensitivity.
  • To compare the anti-allergic potential of MHF and MHR.

Main Methods:

  • Synthesis of MHF and MHR from heparin.
  • Evaluation of MHF and MHR in a rat model of homologous passive cutaneous anaphylaxis.
  • Assessment of MHF and MHR effects on histamine and compound 48/80-induced reactions in mice.

Main Results:

  • MHF significantly inhibited 48-hour homologous passive cutaneous anaphylaxis in rats.
  • MHF prolonged survival time in mice treated with lethal compound 48/80 but did not affect histamine-induced mortality.
  • MHR demonstrated no inhibitory effect on type I hypersensitivity.

Conclusions:

  • MHF's anti-allergic action is attributed to reduced or delayed histamine release from mast cells.
  • MHF exhibits potential as a powerful anti-allergic therapeutic agent.
  • MHF offers a promising alternative for managing type I allergic reactions.
Keywords:
Medium molecular weight heparinyl arginine (MHR)Medium molecular weight heparinyl phenylalanine (MHF)Type I hypersensitivity

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