Anti-AQP1 monoclonal antibody, clone 8E22

Aquaglyceroporins, belonging to the family of aquaporins (AQPs), are integral plasma membrane proteins permeable to water and glycerol that have emerged as key players in obesity. The aim of this study was to investigate the expression profile of AQPs in undifferentiated and differentiated 3T3-L1 cells and to investigate the changes in expression of aquaglyceroporins in 3T3-L1 cells differentiated into adipocytes and subjected to lipopolysaccharide (LPS) mimicking inflammation occurring during obesity. Furthermore, the study aimed at identifying the signaling cascade involved in the regulation of aquaglyceroporins expression upon LPS stimulation. 3T3-L1 cells were grown as undifferentiated cells (UDC; preadipocytes) or cells differentiated into adipocytes (DC, adipocytes). DC were incubated in the presence or absence of LPS with or without inhibitors of various protein kinases. AQPs mRNA expression levels were measured by real-time quantitative polymerase chain reaction (RT-qPCR). AQP1, AQP2, AQP3, AQP9 and AQP11 mRNA were expressed in both UDC and DC, whereas AQP4, AQP7 and AQP8 mRNA were expressed only in DC. In DC, LPS up-regulated AQP3 mRNA levels (p < 0.05) compared to control; these effects were inhibited by CLI095, SP600125 and BAY11-7082 (p < 0.05). LPS decreased both AQP7 and AQP11 mRNA levels (p < 0.01) in DC as compared to control; this decrease was inhibited by CLI095 and BAY11-7082 (p < 0.05) and additionally by SP00125 for AQP7 (p < 0.05). SB203580 had no effect on LPS-induced AQP3, AQP7 and AQP11 mRNA levels modulations. In conclusion, our results clearly show that many AQPs are expressed in murine 3T3-L1 adipocytes. Moreover, in DCs, LPS led to decreased AQP7 and AQP11 mRNA levels but to increased AQP3 mRNA levels, resulting from the Toll-like receptor 4 (TLR4)-induced activation of JNK and/or NF kappa B pathway.

Introduction: The kidney develops from two mesodermal primordia. Aquaporin 1 (AQP1) is a membrane protein characteristic to epithelial and endothelial cell of the human body. The Pax family of genes encodes transcription factors with important role in intrauterine development. Connexins are transmembrane proteins found in gap junctions. We monitored the changes in the expression of AQP1, paired box gene 2 (PAX2), paired box gene 8 (PAX8), connexin 36 (Cx36) and connexin 43 (Cx43) proteins in fetal renal tissue. Materials and Methods: We studied 34 post mortem fetuses of 9 to 24 weeks from the Laboratory of Pathology, Emergency County Hospital of Targu Mures, Romania, using immunohistochemistry. Results: AQP1 expression appeared in the apical and basolateral parts of cells, lining the proximal convoluted tubules and the descending limb of Henle's loop, then in the tubule pole of Bowman's capsule also. Nuclear expression of PAX2 was observed in structures developed both from the ureteric bud and the metanephric mesenchyme, and of PAX8 was observed in the proximal convoluted tubule's epithelium, Henle's loop, and collecting ducts. Cytoplasmic expression of Cx36 was localized to nephrons in different developmental stages, glomerular vessels and collecting ducts, and of Cx43 was localized to the endothelium of glomerular and peritubular vessels, as well as to the epithelium of the proximal tubules. Discussions and Conclusions: Nephrogenesis begins in the embryonic period, and continues into the fetal period as well. It is regulated by a wide array of markers. The current study supplements literature data regarding immunoexpression of these markers during renal development in the fetal period.