Layla Al-Nakkash, Ph.D.

Chair, Physiology
Glendale, AZ

Home / Academics / Our Faculty / Layla Al-Nakkash, Ph.D.


The research in my lab is primarily concerned with understanding the effects of dietary genistein and other nutriceuticals (and exercise) on intestinal function.

Genistein is an isoflavonic phytoestrogen found naturally in soy, and a known activator of the CFTR chloride channel. Cystic fibrosis (CF) is an inherited disease in which epithelia are adversely affected by loss of proper CFTR function (i.e. sweat duct, pancreas, vas deferens, airway and intestine). \We have shown that consuming dietary genistein increases basal and cAMP-mediated chloride secretion in female wild-type (Wt) murine jejuna and in the well established DeltaF508-CF mouse dietary genistein eliminates the dependence of CF mice for laxatives.  Current work is aimed to evaluate how genistein mediates  benficial effect on survival and weight gain in CF mice.   We have shown that diabetic/obese ob/ob mice have significantly reduced jejunal basal chloride secretion, and furthermore, we demonstrate that consuming genistein-diet will rescue this deficit in basal secretion via influences on intestinal ion transporters.  Recent work in my lab is aimed to evaluate the influence of genistein and exercise in mice fed a high-fat/high-sugar (HFHS) diet, a model of diet-induced diabetic obesity, known to lead to Alzheimer's like pathology. In this model we are examining the gut brain axis.

Current studies in the lab are aimed at determining the mechanism(s) of action of genistein on intestinal function in Wt, CF, ob/ob and HFHS-fed mice, and importantly understanding the sex-dependent differences observed.

Chair, Physiology

Glendale, AZ

Arizona College of Osteopathic Medicine
College of Graduate Studies - AZ


Biomedical Sciences (M.A.)
Biomedical Sciences (M.B.S.)
Dental Medicine
Entry into Practice Doctor of Nurse Anesthesia Practice
Post Master's Doctor of Nurse Anesthesia Practice (D.N.A.P.)
Nurse Anesthesia Practice (M.S.)
Osteopathic Medicine
Physical Therapy
Physician Assistant Studies
Podiatric Medicine
Veterinary Medicine

Call My


Send Me
a Message


UK. | 1993 | Ph.D.
UK. | 1988 | B.S.

Courses Taught

PHYSG 1521/1523 Medical Physiology I- (Osteopathic medical students and Podiatric medical students).

PHYSG 1532/1534 Medical Physiology II- (Osteopathic medical students and Podiatric medical students).

PHYSG 1502 (Pharmacy students).

PHYSG 1571 (NA, PA, PT, MA and MBS students)


Our overal lab goal is to understand and identify the mechanisms of action of dietary genistein on the gut-brain axis in various murine models of clinically relevant diseases: cystic fibrosis, diabetes (ob/ob and high fat/high sugar-fed), and Alzheimer's.   

We routinely use the following techniques: Ussing chamber electrophysiology, gastrointestinal motility and contractility, histology, western blot, pcr.


  1. S. Rockwood,  D. Mason, R. Lord, P. Lamar, W. Prozialeck, T. Banayat and L. Al-Nakkash. (2019). Genistein diet improves body weight, serum glucose and triglyceride levels in both male and female ob/ob mice. Diabetes Metabolic Syndrome & Obesity. 12:2011-2021.
  2. Olson, J., J. Rinehart, J.J.Spiegel and L. Al-Nakkash. (2019). Student perception on the integration of simulation experiences into human physiology curricula. Adv. in Physiology Educ. 43: 332-338.
  3. Crawford, M, C. Whisner, L. Al-Nakkash and K.L. Sweazea. (2019). Six-week high fat diet alters the gut microbiome and promotes cecal inflammation, endotoxin production and simple steatosis  in male rats. Lipids Feb;54(2-3):119-131. doi: 10.1002/lipd.12131.
  4. Sandoval-Skeet, N, J.A. Kaufman, M. J. Castro and L. Al-Nakkash. (2018). Genistein diet does not modify crypt morphology in the ob/ob mouse jejunum: a comparison of cryostat and clearing techniques. Diabetes Metabolic Syndrome & Obesity. Nov 29, 11: 863-873. doi: 10.2147/DMSO.S182501.
  5. Lord R., N. Fairbourn, C. Mylavarapu, A. Dbeis, T. Bowman, A. Chandrashekar, T. Banayat, C. Hodges & L. Al-Nakkash. (2018). Consuming dietary genistein improves survival rates of ΔF508-CF female mice.  Nutrients. Oct 3, 10(10), 1418;
  6. Rockwood, S., T.L. Broderick, and L. Al-Nakkash.  (2018). Feeding obese diabetic mice a genistein diet induces thermogenic and metabolic change. J. Medicinal Food. Apr, 21(4) 332-339. doi: 10.1089/jmf.2017.0084.
  7. Kaufman, JA, MJ Catro, N Sandoval-Skeet, & L. Al-Nakkash. (2018). Optical clearing of small intestine for 3-dimensional visualization of cellular proliferation within crypts. J. Anatomy. 232(1):152-157.
  8. Schacht, S., F. Masood, S. Catmull, R, Dolan, R. Altabtabaee, W. Grow & L. Al-Nakkash. (2017). Dietary genistein influences numbers of acetylcholine receptors in female diabetic mouse jejunum. Journal Diabetes Research. 1-9. doi:  10.1155/2017/3568146,
  9. Baker, J., L. Al-Nakkash and M.M. Herbst-Kralovetz. (2017). Estrogen-gut microbiome axis; Physiological and clinical implications. Maturitas. 103:45-53.
  10. Catmull. S., F. Masood, S. Schacht, R. Dolan, D. Stegman, L. Leung and L. Al-Nakkash. (2016). Dietary genistein rescues reduced basal chloride secretion in diabetic jejunum via sex-dependent mechanisms. Cell. Physiol & Biochem. 40: 335-346.

Full list of publications:


The American Physiological Society.

The Arizona Physiological Society.

The Physiological Society.


DAREF (2019, 2018, 2017, 2016)

Midwestern-Arizona Alzheimer's Association (2018-19, 2017-18, 2016-17) 

Soy Health (2014-15, 2011-13)

NIH-R15 ( 2007-11)