Stress levels of glucocorticoids inhibit LHß-subunit gene expression in gonadotrope cells.

Increased glucocorticoid secretion is a common response to stress and has been implicated as a mediator of reproductive suppression upon the pituitary gland. We utilized complementary in vitro and in vivo approaches in the mouse to investigate the role of glucocorticoids as a stress-induced intermediate capable of gonadotrope suppression. Repeated daily restraint stress lengthened the ovulatory cycle of female mice and acutely reduced GnRH-induced LH secretion and synthesis of LH ß-subunit (LHß) mRNA, coincident with increased circulating glucocorticoids. Administration of a stress level of glucocorticoid, in the absence of stress, blunted LH secretion in ovariectomized female mice, demonstrating direct impairment of reproductive function by glucocorticoids. Supporting a pituitary action, glucocorticoid receptor (GR) is expressed in mouse gonadotropes and treatment with glucocorticoids reduces GnRH-induced LHß expression in immortalized mouse gonadotrope cells. Analyses revealed that glucocorticoid repression localizes to a region of the LHß proximal promoter, which contains early growth response factor 1 (Egr1) and steroidogenic factor 1 sites critical for GnRH induction. GR is recruited to this promoter region in the presence of GnRH, but not by dexamethasone alone, confirming the necessity of the GnRH response for GR repression. In lieu of GnRH, Egr1 induction is sufficient for glucocorticoid repression of LHß expression, which occurs via GR acting in a DNA- and dimerization-independent manner. Collectively, these results expose the gonadotrope as an important neuroendocrine site impaired during stress, by revealing a molecular mechanism involving Egr1 as a critical integrator of complex formation on the LHß promoter during GnRH induction and GR repression.

Delivery of siRNA and other macromolecules into skin and cells using a peptide enhancer.

Delivery of macromolecules into cells and tissues such as skin is a major challenge. This obstacle poses a particular challenge for the delivery of siRNA where cellular and tissue level transport barriers need to be overcome. siRNAs are potential therapeutics for various dermatological diseases including psoriasis, atopic dermatitis, and cancer; however, their utility is limited by their low absorption across the stratum corneum (SC) and into viable cells of skin. Here, we address this challenge using a peptide identified by phage display termed skin penetrating and cell entering (SPACE) peptide. In vitro studies indicated that the SPACE peptide, when conjugated to cargoes such as small molecules and proteins, was able to facilitate their penetration across the SC into epidermis and dermis. The peptide also exhibited increased penetration into various cells including keratinocytes, fibroblasts, and endothelial cells, likely through a macropinocytosis pathway. The ability of SPACE peptide to deliver siRNA was tested in vivo using two targets, interleukin-10 and GAPDH. Conjugation of the peptide to siRNA led to their enhanced absorption into skin and knockdown of corresponding protein targets.

Community Pharmacy Use Patterns of Women with HIV and Women At Risk for HIV in the San Francisco Bay Area.

BACKGROUND: Community pharmacies play a key role in the care of patients when dispensing antiretroviral therapy. The primary objective of this study was to describe patterns of community pharmacy use of women enrolled in the San Francisco site of the Women's Interagency HIV Study (WIHS). The secondary objective was to determine whether the number of pharmacies a patient uses is associated with specific patient characteristics or virologic outcomes in HIV positive women. OBJECTIVES: The primary objective was to determine factors which were associated with using multiple dispensing pharmacies to obtain medications in a population of HIV+ and at-risk women. The secondary objective was to determine whether use of multiple pharmacies was associated with immunologic or virologic changes for the subset of HIV+ women. METHODS: A survey on community pharmacy use was distributed to San Francisco WIHS participants from 2004-2007. Poisson, linear, and logistic regression methods were used to determine associations between specific patient characteristics and use of multiple dispensing pharmacies and associations between multiple pharmacy use and CD4+ cell count or viral load changes. RESULTS: There was a trend towards an association between HIV status and use of multiple pharmacies (IRR=1.23; 95% CI 1.00-1.51, p =0.05). In multivariable analyses of HIV positive women, use of additional pharmacies (over the primary pharmacy) during the study period was not associated with statistically significant changes in CD4+ count or viral load. CONCLUSION: HIV positive participants may tend to use multiple pharmacies more frequently than their HIV negative counterparts, though this practice does not appear to be associated with poorer immunologic or virologic outcomes. Future studies should be conducted to determine whether different patient patterns of community pharmacy use affect HIV treatment outcomes.