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Sustained Administration of β-cell Mitogens to Intact Mouse Islets Ex Vivo Using Biodegradable Poly(lactic-co-glycolic acid) Microspheres
Published on: November 5, 2016
Poly(ester amide) blend microspheres for oral insulin delivery.
Pan He1, Huaiyu Liu, Zhaohui Tang
1Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
International Journal of Pharmaceutics
|July 24, 2013
Summary
This study created new oral insulin microspheres using biodegradable poly(ester amide) (PEA) blends. These microspheres effectively deliver insulin orally, improving bioavailability and controlling blood glucose in diabetic rats.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Nanotechnology
Background:
- Oral insulin delivery remains a significant challenge due to insulin's degradation in the gastrointestinal tract.
- Biodegradable polymers offer potential for protecting therapeutic proteins during oral administration.
- Poly(ester amide)s (PEAs) are versatile biomaterials with tunable properties for drug encapsulation.
Purpose of the Study:
- To develop and characterize novel oral insulin formulations using a blend of biodegradable poly(ester amide)s (PEAs).
- To investigate the role of pH-responsive PEA-COOH and absorption-enhancing Arg-PEA in microsphere performance.
- To evaluate the efficacy of the developed microspheres for oral insulin delivery in vitro and in vivo.
Main Methods:
- Synthesis and characterization of L-lysine-/L-leucine-based PEA with pendant COOH groups (PEA-COOH) and arginine-based PEA (Arg-PEA).
- Fabrication of PEA-COOH/Arg-PEA blend microspheres encapsulating insulin.
- In vitro evaluation of microsphere morphology, insulin loading, and release profiles in simulated gastric and intestinal fluids.
- In vivo assessment of blood glucose-lowering effects and oral bioavailability in diabetic and healthy rats, respectively.
Main Results:
- PEA-COOH/Arg-PEA blend microspheres demonstrated effective protection of encapsulated insulin in simulated gastric conditions.
- Microspheres exhibited rapid and sustained insulin release in simulated intestinal fluid.
- Oral administration of insulin-loaded microspheres significantly suppressed blood glucose levels in diabetic rats for 10 hours.
- Improved oral bioavailability of insulin reached 5.89±1.84% in healthy rats.
Conclusions:
- Biodegradable PEA blend microspheres are effective vehicles for oral insulin delivery.
- The formulation successfully protects insulin and enhances its oral absorption.
- This approach shows promise for developing practical oral insulin therapies.
Keywords:
Arg-PEABlend microspheresCLSMDMADMFDMSOEEESEMFITCGIL0.2L0.2–30AN,N-dimethylformamideOral insulin deliveryP(MAA-g-EG)PEAPEA-COOHPEA-COOH with 20% (molar content) of leucine-based monomerPoly(ester amide)S/O/OSCSDSSEMSTZSpan83arginine-based poly(ester amide)blend microspheres containing 30% Arg-PEA and 70% L0.2 by weightdimethyl acetamidedimethyl sulfoxideencapsulation efficiencyenvironmental scanning electron microscopyfluorescein isothiocyanategastrointestinallaser scanning confocal microscopypH sensitivitypoly(ester amide)poly(ester amide) with pendant COOH groupspoly(methacrylic-g-ethylene glycol)scanning electron microscopysodium dodecyl sulphatesolid-in-oil-in-oilsorbitan sesquioleatestreptozotocinsubcutaneous
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