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1.  GENDER DIFFERENCES IN BRAIN SUSCEPTIBILITY TO OXIDATIVE STRESS ARE MEDIATED BY LEVELS OF PARAOXONASE-2 (PON2) EXPRESSION 
Paraoxonase 2 (PON2), a member of a gene family that also includes PON1 and PON3, is expressed in most tissues, including the brain. In mouse brain, PON2 levels are highest in dopaminergic areas (e.g. striatum), and are higher in astrocytes than in neurons. PON2 is primarily located in mitochondria and exerts a potent antioxidant effect, protecting mouse CNS cells against oxidative stress. The aim of this study was to characterize PON2 expression and functions in the brains of male and female mice. Levels of PON2 (protein, mRNA, and lactonase activity) were higher in brain regions and cells of female mice. Astrocytes and neurons from male mice were significantly more sensitive (by 3–4-fold) to oxidative stress-induced toxicity than the same cells from female mice. Glutathione levels did not differ between genders. Importantly, no significant gender differences in susceptibility to the same oxidants were seen in cells from PON2−/− mice. Treatment with estradiol induced a time- and concentration-dependent increase in the levels of PON2 protein and mRNA in male (4.5-fold) and female (1.8-fold) astrocytes, which was dependent on activation of estrogen receptor alpha. In ovariectomized mice, PON2 protein and mRNA were decreased to male levels in brain regions and in liver. Estradiol protected astrocytes from wild-type mice against oxidative stress-induced neurotoxicity, but did not protect cells from PON2−/− mice. These results suggest that PON2 is a novel major intracellular factor that protects CNS cells against oxidative stress, and confers gender-dependent susceptibility to such stress. The lower expression of PON2 in males may have broad ramifications for susceptibility to diseases involving oxidative stress, including neurodegenerative diseases.
doi:10.1016/j.freeradbiomed.2013.01.019
PMCID: PMC3622778  PMID: 23376469
Paraoxonase 2; oxidative stress; gender difference; estrogen; neuroprotection
2.  The significance of galectin-3 as a new basal cell marker in prostate cancer 
Cell Death & Disease  2013;4(8):e753-.
Prostate cancer may originate from distinct cell types, resulting in the heterogeneity of this disease. Galectin-3 (Gal-3) and androgen receptor (AR) have been reported to play important roles in the progression of prostate cancer, and their heterogeneous expressions might be associated with different cancer subtypes. Our study found that in various prostate cancer cell lines Gal-3 expression was always opposite to AR expression and other luminal cell markers but consistent with basal cell markers including glutathione S-transferase-π and Bcl-2. This expression pattern was confirmed in human prostate cancer tissues. Our results also showed that prostate cancer cells positive with basal cell markers were more aggressive. Downregulation of Gal-3 expression resulted in increased apoptotic potential and decreased metastasis potential of prostate cancer cells. Our findings demonstrate for the first time that Gal-3 may serve as a new marker for basal characteristics of prostate cancer epithelium. This study helps us to better understand the heterogeneity of prostate cancer. The clinical significance of this study lies in the application of Gal-3 to distinguish prostate cancer subtypes and improve treatment efficacy with designed personalized therapy.
doi:10.1038/cddis.2013.277
PMCID: PMC3763439  PMID: 23907467
Gal-3; AR; prostate cancer; basal marker
3.  Mice immunized by primary vaginal Candida albicans infection develop acquired vaginal mucosal immunity. 
Infection and Immunity  1995;63(2):547-553.
It has been postulated that systemic cell-mediated immunity (CMI) is an important host defense mechanism against Candida infections of the vagina. However, in an estrogen-dependent murine model of experimental vaginal candidiasis, we recently showed that systemic Candida-specific Th1-type CMI induced by immunization with Candida culture filtrate antigen had no effect on vaginal Candida population levels during the course of a vaginal infection. In the present study, mice given a second vaginal inoculation in the presence of peripheral Candida-specific Th1-type CMI induced by prior vaginal infection had anamnestic-type increased delayed-type hypersensitivity (DTH) responses, concomitant with significantly fewer Candida organisms in the vagina than in primary-infected mice. In addition, organisms in secondary-infected mice were fragmented and superficial penetration into the epithelium was reduced. The systemic presence of Candida-specific T suppressor (Ts) cells that significantly suppressed the infection-derived anamnestic DTH reactivity did not abrogate the protective effect in the vagina. Additional experiments showed that vaginally immunized mice were not protected from gastrointestinal or systemic candidiasis and, in contrast to mice with a second vaginal infection, did not demonstrate anamnestic DTH reactivity. These results suggest that a moderate level of local protection against a Candida vaginal infection can be achieved by vaginal immunization but that the protective role of acquired peripheral Candida-specific Th1-type reactivity at the vaginal mucosa appears to be limited.
PMCID: PMC173030  PMID: 7822020

Results 1-4 (4)