Comparative assessment of estrogenic responses with relevance to the metabolic syndrome and to menopausal symptoms in wild-type and aromatase-knockout mice

Knockout of the Cyp-19 gene (aromatase) renders mice to have insufficient endogenous estrogen production and contributes to the development of symptoms related the metabolic syndrome, including excess adiposity and insulin resistance. This study comparatively assessed the estrogen responsiveness in animal models of genetical versus surgical (ovariectomy) origin of estrogen deficiency. Evaluation of physiological parameters and gene expression pattern in response to estrogens revealed differences in estrogen responsiveness between aromatase deficient and castrated or intact wild-type mice. ArKO mice had a significantly higher bodyweight than matched ovariectomized wild-type mice. The weight of the completely regressed uterus following ovariectomy was higher than the uterine weight of ArKO mice. Further, alterations in metabolic parameters like increased serum leptin levels and decreased plasma glucose levels in genetically deficient mice became apparent. Finally, expression pattern of estrogen responsive genes differed in the two experimental models of estrogen deficiency. Both, in uterine and adipose tissues the regulation of expression of some genes either was inversed of regulation or considerably differed in the magnitude of the response in the two models. Our studies demonstrate that the cause of estrogen deficiency significantly impacts on estrogen responsiveness and may be of relevance for investigations on aspects of estrogen deficiency and metabolic and/or menopausal symptoms.     

Oramoeba fumarolia gen. nov., sp. nov., a new marine heterolobosean amoeboflagellate growing at 54 °C

An amoeba strain was isolated from marine sediment taken from the beach near a fumarole in Italy. The trophozoites of this new marine species transforms into flagellates with variable numbers of flagella, from 2 to 10. The strain forms round to oval cysts. This thermophilic amoeboflagellate grows at temperatures up to 54 °C. Molecular phylogenetic analysis of the small subunit ribosomal DNA (SSU rDNA) places the amoeboflagellate in the Heterolobosea. The closest relatives are Stachyamoeba sp. ATCC50324, a strain isolated from an ocean sample, and Vrihiamoeba italica, a recent isolate from a rice field. Like some other heterolobosean species, this new isolate has a group I intron in the SSU rDNA. Because of the unique place in the molecular phylogenetic tree, and because there is no species found in the literature with similar morphological and physiological characteristics, this isolate is considered to be a new genus and a new species, Oramoeba fumarolia gen. nov., sp. nov.     

Older poor-sleeping women display a smaller evening increase in melatonin secretion and lower values of melatonin and core body temperature than good sleepers

Melatonin concentration and core body temperature (CBT) follow endogenous circadian biological rhythms. In the evening, melatonin level increases and CBT decreases. These changes are involved in the regulation of the sleep-wake cycle. Therefore, the authors hypothesized that age-related changes in these rhythms affect sleep quality in older people. In a cross-sectional study design, 11 older poor-sleeping women (aged 62-72 yrs) and 9 older good-sleeping women (60-82 yrs) were compared with 10 younger good-sleeping women (23-28 yrs). The older groups were matched by age and body mass index. Sleep quality was assessed by the Pittsburgh Sleep Quality Index questionnaire. As an indicator of CBT, oral temperature was measured at 1-h intervals from 17:00 to 24:00?h. At the same time points, saliva samples were collected for determining melatonin levels by enzyme-linked immunosorbent assay (ELISA). The dim light melatonin onset (DLMO), characterizing the onset of melatonin production, was calculated. Evening changes in melatonin and CBT levels were tested by the Friedman test. Group comparisons were performed with independent samples tests. Predictors of sleep-onset latency (SOL) were assessed by regression analysis. Results show that the mean CBT decreased in the evening from 17:00 to 24:00?h in both young women (from 36.57°C to 36.25°C, p < .001) and older women (from 36.58°C to 35.88°C, p < .001), being lowest in the older poor sleepers (p < .05). During the same time period, mean melatonin levels increased in young women (from 16.2 to 54.1 pg/mL, p < .001) and older women (from 10.0 to 23.5 pg/mL, p < .001), being lowest among the older poor sleepers (from 20:00 to 24:00?h, p < .05 vs. young women). Older poor sleepers also showed a smaller increase in melatonin level from 17:00 to 24:00?h than older good sleepers (mean?±?SD: 7.0?±?9.63 pg/mL vs. 15.6?±?24.1 pg/mL, p = .013). Accordingly, the DLMO occurred at similar times in young (20:10?h) and older (19:57?h) good-sleeping women, but was delayed ～50?min in older poor-sleeping women (20:47?h). Older poor sleepers showed a shorter phase angle between DLMO and sleep onset, but a longer phase angle between CBT peak and sleep onset than young good sleepers, whereas older good sleepers had intermediate phase angles (insignificant). Regression analysis showed that the DLMO was a significant predictor of SOL in the older women (R(2)?=?0.64, p < .001), but not in the younger women. This indicates that melatonin production started later in those older women who needed more time to fall asleep. In conclusion, changes in melatonin level and CBT were intact in older poor sleepers in that evening melatonin increased and CBT decreased. However, poor sleepers showed a weaker evening increase in melatonin level, and their DLMO was delayed compared with good sleepers, suggesting that it is not primarily the absolute level of endogenous melatonin, but rather the timing of the circadian rhythm in evening melatonin secretion that might be related to disturbances in the sleep-wake cycle in older people.     

Peroxisome proliferator-activated receptor β/δ agonism protects the kidney against ischemia/reperfusion injury in diabetic rats

Diabetes is an important risk factor for ischemic acute kidney injury, whose pharmacological treatment remains an unmet medical need. The peroxisome proliferator-activated receptor (PPAR) β/δ is highly expressed in the kidney, although its role has not yet been elucidated. Here, we used an in vivo model of renal ischemia/reperfusion (I/R) in streptozotocin-induced diabetic rats (i) to evaluate whether diabetes increases kidney susceptibility to I/R injury and (ii) to investigate the effects of PPARβ/δ activation. The degree of renal injury (1h ischemia/6h reperfusion) was significantly increased in diabetic rats compared with nondiabetic littermates. PPARβ/δ expression was increased after I/R, with the highest levels in diabetic rats. Administration of the selective PPARβ/δ agonist GW0742 attenuated the renal dysfunction, leukocyte infiltration, and formation of interleukin-6 and tumor necrosis factor-α. These effects were accompanied by an increased expression of the suppressor of cytokine signaling (SOCS)-3, which plays a critical role in the cytokine-activated signaling pathway. The beneficial effects of GW0742 were attenuated by the selective PPARβ/δ antagonist GSK0660. Thus, we report herein that PPARβ/δ activation protects the diabetic kidney against I/R injury by a mechanism that may involve changes in renal expression of SOCS-3 resulting in a reduced local inflammatory response.     

Synthesis, pharmacophore modeling and in vitro activity of 10,11-dihydrodibenzo[b,f]oxepine-4-carboxamide derivatives as novel and potent antagonists of the prostaglandin EP4 receptor

The construction of a EP(4) antagonists pharmacophore model and the discovery of a highly potent oxepinic series of EP(4) antagonists is discussed. Compound 1a exhibits an excellent selectivity profile toward EP(2) receptor subtype and low cytochrome P450 inhibition potential.     

Multitargeted drugs discovery: balancing anti-amyloid and anticholinesterase capacity in a single chemical entity

Memoquin (1) is a lead compound multitargeted against Alzheimer’s disease (AD). It is an AChE inhibitor, free-radical scavenger, and inhibitor of amyloid-β (Aβ) aggregation. A new series of 1 derivatives was designed and synthesized by linking its 2,5-diamino-benzoquinone core with motifs that are present in the structure of known amyloid binding agents like curcumin, the benzofuran derivative SKF64346, or the benzothiazole bearing compounds KHG21834 and BTA-1. The weaker AChE inhibitory potencies and the concomitant nearly equipotent anti-amyloid activities of the new compounds with respect to 1 resulted in a more balanced biological profile against both targets. Selected compounds turned out to be effective Aβ aggregation inhibitors in a cell-based assay. By properly combining two or more distinct pharmacological properties in a molecule, we can achieve greater effectiveness compared to single-targeted drugs for investigating AD.     

Recombinant plant-expressed tumour-associated MUC1 peptide is immunogenic and capable of breaking tolerance in MUC1.Tg mice

The human epithelial mucin MUC1 is a heavily glycosylated transmembrane protein that is overexpressed and aberrantly glycosylated on over 90% of human breast cancers. The altered glycosylation of MUC1 reveals an immunodominant peptide along its tandem repeat (TR) that has been used as a target for tumour immunotherapy. In this study, we used the MUC1 TR peptide as a test antigen to determine whether a plant-expressed human tumour-associated antigen can be successfully expressed in a plant system and whether it will be able to break self-antigen tolerance in a MUC1-tolerant mouse model. We report the expression of MUC1 TR peptide fused to the mucosal-targeting Escherichia coli enterotoxin B subunit (LTB-MUC1) in a plant host. Utilizing a rapid viral replicon transient expression system, we obtained high yields of LTB-MUC1. Importantly, the LTB-MUC1 fusion protein displayed post-translational modifications that affected its antigenicity. Glycan analysis revealed that LTB-MUC1 was glycosylated and a MUC1-specific monoclonal antibody detected only the glycosylated forms. A thorough saccharide analysis revealed that the glycans are tri-arabinans linked to hydroxyprolines within the MUC1 tandem repeat sequence. We immunized MUC1-tolerant mice (MUC1.Tg) with transiently expressed LTB-MUC1, and observed production of anti-MUC1 serum antibodies, indicating breach of tolerance. The results indicate that a plant-derived human tumour-associated antigen is equivalent to the human antigen in the context of immune recognition.