Mark A. Yorek, PhD

Contact Information

Office: 204 40 VAMC 
Faculty Profile

Brief description of current research:

Dr. Yorek’s research focuses primarily on vascular and neural disease related to obesity and diabetes. They are interested in determining the etiology of peripheral neuropathy associated with these conditions. An overall goal of their studies is to determine the role of vascular dysfunction in obesity- and diabetic-neuropathy and the mechanism responsible for vascular dysfunction. Briefly, they have developed the methodology to examine the effect of diabetes on vasodilation of blood vessels that provide circulation to the sciatic nerve and the retina. Combined with the examination of motor and sensory nerve conduction velocity, neuronal blood flow in the sciatic nerve, and sensory nerve perception they are investigating the etiology of diabetic neuropathy with emphasis on vascular disease. In addition, they have also been conducting studies examining impairment of innervation of the cornea as a marker for obesity- and diabetic-neuropathy. Recently, they have developed a novel sensitivity assay for corneal nerves that can be used in animals as well as humans.  Using animal models of obesity and diabetes they have demonstrated that loss of corneal nerves function and density especially those innervating the cornea epithelium occurs early in disease. They have also shown that in the sub-epithelial layer of the cornea early detection of nerve loss can be achieved by examining the region of the inferior whorl. These results have translational importance for the early detection of obesity- and diabetic-neuropathy that could be used for examining the progression and repair of neuropathy in patients. In this regard they have been conducting studies in the use of menhaden oil (fish oil), a natural source for n-3 fatty acids, for the treatment of obesity- and diabetic-neuropathy. They have demonstrated that treating rodent models of pre-diabetes and type 2 diabetes with menhaden oil improves insulin resistance and vascular and neural complications. They believe that the mechanism(s) responsible for the beneficial effects of menhaden oil is the reduction in the n-6 to n-3 fatty acid ratio and production of resolvins and neuroprotectin, metabolites of n-3 fatty acids that have anti-inflammatory and neuroprotection properties. Studies are ongoing to investigate the mechanism(s) responsible for the beneficial effects of fish oils in obesity and diabetes. In addition clinical studies are being designed to test the benefits of fish oil treatment in subjects with diabetes.  The Yorek laboratory is also collaborating with Novartis and Novo Nordisk testing new compounds for the treatment of diabetic neuropathy.

3 most recent diabetes/obesity/metabolism publications:

  • Effect of Fish Oil vs. Resolvin D1, E1, Methyl Esters of Resolvins D1 or D2 on Diabetic Peripheral Neuropathy. Obrosov A, Coppey LJ, Shevalye H, Yorek MA. J Neurol Neurophysiol. 2017;8(6). pii: 453. doi: 10.4172/2155-9562.1000453. Epub   2017 Dec 24. PMID: 29423332
  • Is Fish Oil a Potential Treatment for Diabetic Peripheral Neuropathy? Yorek MA. Curr Diabetes Rev. 2017 May 22. doi: 10.2174/1573399813666170522155327. [Epub ahead of print] PMID: 28530530
  • Impaired Corneal Sensation and Nerve Loss in a Type 2 Rat Model of Chronic Diabetes Is Reversible With Combination Therapy of Menhaden Oil, α-Lipoic Acid, and Enalapril. Davidson EP, Coppey LJ, Shevalye H, Obrosov A, Kardon RH, Yorek MA. Cornea. 2017 Jun;36(6):725-731. doi: 10.1097/ICO.0000000000001182. PMID: 28476051

Quote:

"Someday I hope to understand the work we do well enough to explain it to myself."

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