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Patricia McLaughlin, MS, DEd

Patricia McLaughlin, MS, DEd

Distinguished Professor, Department of Neural and Behavioral Sciences
Penn State Neuroscience Institute
Scientific Program:Next-Generation Therapies

Research Interests

Dr. Patricia McLaughlin’s research focuses on the Opioid Growth Factor (OGF) – OGF receptor (OGFr) pathway and mechanisms of action in homeostasis and disease. Early collaborative work with Dr. Ian Zagon resulted in the identification of [Met5]-enkephalin as the endogenous ligand for the OGF-OGFr pathway. Subsequently, a new nuclear-associated receptor was identified and termed OGFr. One group in the laboratory has characterized and cloned the OGFr gene in human, mouse and rat. Protein chemistry studies, along with structural biology, determined that the OGFr is a uniquely unstructured nuclear receptor. The mechanism of action was determined to involve inhibition of DNA synthesis with the specific mechanistic pathway involving upregulation of cyclin-dependent inhibitory kinases p16 and p21. OGF action is receptor-mediated, reversible, and not associated with apoptosis/necrosis. OGF is tissue non-specific and has been identified in proliferating cells and tissues derived from all 3 dermal layers.

Currently, the lab’s work is translational, focusing on disease-based pathways that are characterized by a perturbation in the OGF-OGFr axis. Consequences of receptor blockade of the OGF-OGFr axis are being studied with an emphasis on the etiology and treatment of complications (e.g., delayed wound healing, dry eye, impaired bone composition) arising from long-term diabetes (Type 1 or Type 2). These investigations (humans and animal models) focus on treatment options and utilize confocal microscopy, animal surgery, immunohistochemistry and tissue culture.

In another series of studies, the lab is testing the hypothesis that down-regulation of the inhibitory OGF peptide plays a role in multiple sclerosis and other autoimmune diseases. The lab is also currently validating serum biomarkers and cytokine expression profiles that correspond to changes in behavior and MRI imaging that may be related to disease progression and response to therapy. The clinical and animal research is both qualitative and quantitative in design and is supported by NIH, ADA, TSF (PA) and foundations.

  • Opioid Analgesics
  • Intercellular Signaling Peptides and Proteins
  • Naltrexone
  • methionine-enkephalin receptor
  • Growth
  • Enkephalins
  • Neoplasms
  • Opioid Receptors
  • Cell Proliferation
  • Narcotic Antagonists
  • DNA
  • Brain

Recent Publications


Kumari, R, Kareem, ZY & McLaughlin, PJ 2023, 'Acute Low Dose Naltrexone Increases β-Endorphin and Promotes Neuronal Recovery Following Hypoxia-Ischemic Stroke in Type-2 Diabetic Mice', Neurochemical Research, vol. 48, no. 9, pp. 2835-2846.
McLaughlin, PJ, West, EA, Grigson, PS & Hobkirk, AL 2023, 'Addiction III: From mouse to man', Brain Research Bulletin, vol. 193, pp. 22-26.
Kareem, ZY, McLaughlin, PJ & Kumari, R 2023, 'Opioid growth factor receptor: Anatomical distribution and receptor colocalization in neurons of the adult mouse brain', Neuropeptides, vol. 99, 102325.
McLaughlin, PJ, Sassani, JW & Zagon, IS 2023, 'Safety study of topical naltrexone therapy for diabetic skin wounds is confirmed in Göttingen mini-pigs', Drug Development Research, vol. 84, no. 6, pp. 1279-1284.


McLaughlin, PJ, Odom, LB, Arnett, PA, Orehek, S, Thomas, GA & Zagon, IS 2022, 'Low-dose naltrexone reduced anxiety in persons with multiple sclerosis during the COVID-19 pandemic', International Immunopharmacology, vol. 113, 109438.


McLaughlin, PJ, Sassani, J, Purushothaman, I & Zagon, IS 2021, 'Naltrexone blockade of OGFr enhances cutaneous wound closure in diabetic rats', Medicine in Drug Discovery, vol. 11, 100098.
Purushothaman, I, Zagon, IS, Sassani, JW & McLaughlin, PJ 2021, 'Ocular surface complications in diabetes: The interrelationship between insulin and enkephalin', Biochemical Pharmacology, vol. 192, 114712.
Purushothaman, I, Zagon, IS, Sassani, J & McLaughlin, PJ 2021, 'Ocular surface complications result from dysregulation of the OGF-OGFr signaling pathway in female diabetic rats', Experimental and Therapeutic Medicine, vol. 22, no. 1, 687.
Purushothaman, I, Zagon, IS, Sassani, JW, Zhou, S & McLaughlin, PJ 2021, 'Sex differences in the magnitude of diabetic ocular surface complications: Role of serum OGF', Physiology and Behavior, vol. 237, 113436.
Patel, C, Zagon, IS, Pearce-Clawson, M & McLaughlin, PJ 2022, 'Timing of treatment with an endogenous opioid alters immune response and spinal cord pathology in female mice with experimental autoimmune encephalomyelitis', Journal of Neuroscience Research, vol. 100, no. 2, pp. 551-563.
Patel, C, Thomas, G, Zomorodi, N, Zagon, IS & McLaughlin, PJ 2021, 'β-endorphin and opioid growth factor as biomarkers of physical ability in multiple sclerosis', Multiple Sclerosis and Related Disorders, vol. 50, 102868.


Zagon, IS, Sassani, JW, Purushothaman, I & McLaughlin, PJ 2021, 'Blockade of OGFr delays the onset and reduces the severity of diabetic ocular surface complications', Experimental Biology and Medicine, vol. 246, no. 5, pp. 629-636.
Zagon, IS, Sassani, JW, Purushothaman, I & McLaughlin, PJ 2020, 'Dysregulation of the OGF–OGFr pathway correlates with elevated serum OGF and ocular surface complications in the diabetic rat', Experimental Biology and Medicine, vol. 245, no. 15, pp. 1414-1421.
Patel, C, Meadowcroft, MD, Zagon, IS & McLaughlin, PJ 2020, '[Met5]-enkephalin preserves diffusion metrics in EAE mice', Brain Research Bulletin, vol. 165, pp. 246-252.