Candidate: Thuy Phuong Tran Program: Master of Science in Biology Date: Monday March 4, 2013 Time: 1:00 p.m. Place: George Mason University, Prince William Campus Bull Run Hall, Room 253
Title: "Molecular
Interactions of Polycystic Ovarian Syndrome (PCOS) With Metabolic
Syndrome and Non-Alcoholic Fatty Liver Disease (NAFLD)"
Thesis
Director:
Dr. Ancha Baranova
Thesis
Committee: Dr. Daniel N. Cox and Dr. Alessandra
Luchini
A
copy of the thesis will be available in the Johnson Center Library. All are invited to attend the defense.
ABSTRACT
Obesity is a common factor involved in both polycystic
ovary syndrome (PCOS) and non-alcoholic fatty liver disease (NAFLD).
Obesity causes NAFLD and aggravates hirsutism and menstrual disorder in
polycystic ovary syndrome (PCOS). Recent findings suggest that women
with PCOS may be at risk for developing NAFLD and conversely, NAFLD
patients may be a risk for PCOS. To assess the literature for
associations between PCOS and NAFLD at molecular level, we performed a
systematic review of peer-reviewed articles related to PCOS and NAFLD.
Articles were summarized and grouped according to different sections
defining interactions of PCOS with metabolic syndrome and NAFLD as well
as common risk factors, pathogenic pathways and treatment options.
Based on the association of PCOS and other metabolic abnormalities,
such as insulin resistance, hyperandrogenism, obesity and NAFLD, the
PCOS candidate genes have been proposed. Closer scrutiny of these genes
placed most of their proteins at the crossroads of three highly inter-
related conditions: metabolic syndrome, obesity and NAFLD. This made
us to postulate that PCOS is, in fact, the ovarian manifestation of
metabolic syndrome, similarly to NAFLD that is currently recognized as
the hepatic manifestation of metabolic syndrome. PCOS and NAFLD
conditions may co-exist and may respond to similar therapeutic
strategies.
In order to untangle the complex relationship between PCOS and NAFLD
experimentally, we analyzed serum biomarkers of apoptosis, select
adipokines and mRNA profile in the visceral adipose tissue of obese
patients. Two clinical cohorts were compared: one with both PCOS and
NAFLD that have not yet progressed to NASH according to their liver
biopsies (N=12) and another, a BMI-matched non-PCOS non-NASH NAFLD
control cohort (N=12). The total serum levels of apoptotic biomarker
M30 were significantly elevated in PCOS patients with liver steatosis
as compared to non-PCOS NAFLD controls (P < 0.02), pointing that
androgen-dependent proapoptotic PCOS environment may directly
contribute to NAFLD progression in these patients. Similarly,
hyperandrogenism may explain an observed PCOS-specific decrease (P <
0.04) in adipose LDLR mRNA expression that may be connected to the
proneness of PCOS patients with concomitant liver disease to the
progression to NASH. The levels of mRNA encoding
angiogenesis-associated GSK-3B interacting protein ninein were
significantly increased in PCOS adipose (P < 0.007). In entire NAFLD
cohort, the levels of the resistin were positively correlated with
expression levels of LDLR and prothrombin time. In regards to all these
parameters, the studies of larger cohorts of PCOS patients are needed,
including subgroups without any histological sign of the liver disease
and these without an excess of androgens.