Angiopoietin-1/Tie2 signaling pathway contributes to the therapeutic effect of thymosin β4 on diabetic peripheral neuropathy.

Abstract

Angiopoietin-1 (Ang1) and its receptor Tie2 regulate vascular function. Our previous study demonstrated that thymosin beta 4 (Tβ4) ameliorates neurological function of diabetic peripheral neuropathy. Mechanisms underlying the therapeutic effect of Tβ4 on diabetic peripheral neuropathy have not been fully investigated. The present in vivo study investigated whether the Ang1/Tie2 signaling pathway is involved in Tβ4-improved neurovascular remodeling in diabetic peripheral neuropathy. Diabetic BKS. Cg-m+/+Leprdb/J (db/db) mice at age 20 weeks were treated with Tβ4 and neutralizing antibody against mouse Tie2 for 4 consecutive weeks. Neurological functional and neurovascular remodeling were measured. Administration of the neutralizing antibody against Tie2 attenuated the therapeutic effect of Tβ4 on improved diabetic peripheral neuropathy as measured by motor and sensory nerve conduction velocity and thermal hypoesthesia compared to diabetic db/db mice treated with Tβ4 only. Histopathological analysis revealed that the neutralizing antibody against Tie2 abolished Tβ4-increased microvascular density in sciatic nerve and intraepidermal nerve fiber density, which were associated with suppression of Tβ4-upregulated occludin expression and Tβ4-reduced protein levels of nuclear factor-κB (NF-κB) and vascular cell adhesion molecule-1 (VCAM1). Our data provide in vivo evidence that the Ang1/Tie2 pathway contributes to the therapeutic effect of Tβ4 on diabetic peripheral neuropathy.

• Authors: Lei Wang, Michael Chopp, Alexandra Szalad, XueRong Lu, Mei Lu, Talan Zhang, Zheng Gang Zhang
• Journal: Neuroscience research (Neurosci Res) Vol. 147 Pg. 1-8 (Oct 2019) ISSN: 1872-8111 [Electronic] Ireland
• PMID: 30326249 (Publication Type: Journal Article)
• Copyright: Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.

Chemical References

• Angiopoietin-1
• Angpt1 protein, mouse
• Blood Glucose
• thymosin beta(4)
• Thymosin
• Receptor, TIE-2
• Tek protein, mouse

Topics

• Angiopoietin-1 (metabolism)
• Animals
• Blood Glucose (drug effects)
• Body Weight (drug effects)
• Diabetes Mellitus, Experimental (complications)
• Diabetic Neuropathies (drug therapy, metabolism)
• Mice
• Mice, Transgenic
• Nerve Fibers (drug effects, pathology)
• Receptor, TIE-2 (antagonists & inhibitors, metabolism)
• Sciatic Nerve (blood supply, pathology)
• Signal Transduction (drug effects)
• Thymosin (pharmacology)