Effect of Methadone Maintenance on Expression of BDNF and CREB Genes in Brain VTA of Male Morphine Treated Rats

Background: Morphine independent reduces the expression level of Brain-derived Neurotrophic Factor (BDNF) and Cyclic-AMP Response Element Binding protein (CREB). BDNF and CREB play a vital role in protecting and regulating the proper functioning of neurons. There has not been any study on the effect of methadone maintenance treatment and its comparison with morphine. Therefore, this study was conducted to examine the effect of methadone maintenance on the expression of BDNF and CREB genes in brain VTA of male morphine treated rats Methods: I Morphine independent reduces the expression level of Brain-derived Neurotrophic Factor (BDNF) and Cyclic-AMP Response Element Binding protein (CREB). BDNF and CREB play a vital role in protecting and regulating the proper functioning of neurons. There has not been any study on the effect of methadone maintenance treatment and its comparison with morphine. Therefore, this study was conducted to examine the effect of methadone maintenance on the expression of BDNF and CREB genes in brain VTA of male morphine treated rats Results: According to the findings of this study, similar to morphine treated group, methadone maintenance in morphine treated animals led to significant reduction in the expression of BDNF and CREB genes at VTA as well as BDNF serum level compared with control group. Conclusion: It was concluded that methadone, like morphine, causes significant reduction in the expression of BDNF and CREB genes in brain VTA area of rat as well as BDNF serum level compared with control group.

Regulation of ytfK by cAMP-CRP Contributes to SpoT-Dependent Accumulation of (p)ppGpp in Response to Carbon Starvation YtfK Responds to Glucose Exhaustion

Guanosine penta- or tetraphosphate (known as (p)ppGpp) serves as second messenger to respond to nutrient downshift and other environmental stresses, a phenomenon called stringent response. Accumulation of (p)ppGpp promotes the coordinated inhibition of macromolecule synthesis, as well as the activation of stress response pathways to cope and adapt to harmful conditions. In Escherichia coli, the (p)ppGpp level is tightly regulated by two enzymes, the (p)ppGpp synthetase RelA and the bifunctional synthetase/hydrolase SpoT. We recently identified the small protein YtfK as a key regulator of SpoT-mediated activation of stringent response in E. coli. Here, we further characterized the regulation of ytfK. We observed that ytfK is subjected to catabolite repression and is positively regulated by the cyclic AMP (cAMP)-cAMP receptor protein (CRP) complex. Importantly, YtfK contributes to SpoT-dependent accumulation of (p)ppGpp and cell survival in response to glucose starvation. Therefore, regulation of ytfK by the cAMP-CRP appears important to adjust (p)ppGpp level and coordinate cellular metabolism in response to glucose availability.

Highly sensitive in vitro bioassay for Luteinizing Hormone and Chorionic Gonadotropin

IIn previous studies, we had shown the synergistic effect of 10-5 M forskolin (FSK) on the detection threshold of the cyclic AMP response to Luteinizing Hormones (LH) and Chorionic Gonadotropins (CG) from various species in the mouse Leydig Tumor cell (mLTC) cell line. Indepedently, we had started to study the effect of 10-12 – 10-6 M OXT also on the cyclic AMP response to LH and CG preparations on these same cells and found an amplifying effect on the luminescence response caused by gonadotropins. The aim was then to explore the effects of 10-12 – 10-6 M OXT on the gonadotropin-induced cAMP response, in the presence or absence of 10 µM FSK to optimize the assay down to a sensitivity compatible with the detection of the circulating concentrations of these hormones in various species. Finally the optimization relies on three independent phenomena: 1/ the inhibition of nucleotide phosphodiesterase by IBMX to avoid cAMP degradation, 2/ the strong synergy of 10 µM forskolin with low concentrations of LH or CG during the 1-hour luminescence measurement and, 3/ the stimulatory effect of 10-8M oxytocin on the amplitude of transfected cAMP-sensitive luciferase response. By doing this, the detectable concentrations are at the 1-10 pg/well (pM range) for the LHs and CGs from various species. The bioactivities of circulating LHs and CGs in blood or urine are therefore expected to be measurable in 10µL-plasma samples from mammalian species and maybe others.

Expression of Endogenous Putative TSH Binding Protein in Orbit

Thyroid stimulating antibodies (TSAB) cause Graves’ disease and contribute to Graves’ Orbitopathy (GO) pathogenesis. We hypothesise that the presence of TSH binding proteins (truncated TSHR variants (TSHRv)) and/or nonclassical ligands such as thyrostimulin (α2β5) might provide a mechanism to protect against or exacerbate GO. We analysed primary human orbital preadipocyte-fibroblasts (OF) from GO patients and people free of GO (non-GO). Transcript (QPCR) and protein (western blot) expression levels of TSHRv were measured through an adipogenesis differentiation process. Cyclic-AMP production by TSHR activation was studied using luciferase-reporter and RIA assays. After differentiation, TSHRv levels in OF from GO were significantly higher than non-GO (p = 0.039), and confirmed in ex vivo analysis of orbital adipose samples. TSHRv western blot revealed a positive signal at 46 kDa in cell lysates and culture media (CM) from non-GO and GO-OF. Cyclic-AMP decreased from basal levels when OF were stimulated with TSH or Monoclonal TSAB (M22) before differentiation protocol, but increased in differentiated cells, and was inversely correlated with the TSHRv:TSHR ratio (Spearman correlation: TSH r = −0.55, p = 0.23, M22 r = 0.87, p = 0.03). In the bioassay, TSH/M22 induced luciferase-light was lower in CM from differentiated GO-OF than non-GO, suggesting that secreted TSHRv had neutralised their effects. α2 transcripts were present but reduced during adipogenesis (p < 0.005) with no difference observed between non-GO and GO. β5 transcripts were at the limit of detection. Our work demonstrated that TSHRv transcripts are expressed as protein, are more abundant in GO than non-GO OF and have the capacity to regulate signalling via the TSHR.

Single-cell analysis of prostaglandin E2-induced human decidual cell in vitro differentiation: A minimal ancestral deciduogenic signal

The decidua is a hallmark of reproduction in many placental mammals. Differentiation of decidual stromal cells is known to be induced by progesterone and the cyclic AMP/protein kinase A (cAMP/PKA) pathway. Several candidates have been identified as the physiological stimulus for adenylyl cyclase activation, but their relative importance remains unclear. To bypass this uncertainty, the standard approach for in vitro experiments uses membrane-permeable cyclic AMP and progestin. We phylogenetically infer that prostaglandin E2 (PGE2) likely was the signal that ancestrally induced decidualization in conjunction with progesterone. This suggests that PGE2 and progestin should be able to activate the core gene regulatory network of decidual cells. To test this prediction we performed a genome-wide study of gene expression in human endometrial fibroblasts decidualized with PGE2 and progestin. Comparison to a cAMP-based protocol revealed shared activation of core decidual genes, and decreased induction of senescence-associated genes. Single-cell transcriptomics of PGE2-mediated decidualization revealed a distinct early activated state transitioning to a differentiated decidual state. PGE2-mediated decidualization was found to depend upon progestin-dependent induction of PGE2 receptor 2 (PTGER2) which in turn leads to PKA activation upon PGE2 stimulation. Progesterone-dependent induction of PTGER2 is absent in opossum, an outgroup taxon of placental mammals which is incapable of decidualization. Together, these findings suggest that the origin of decidualization involved the evolution of progesterone-dependent activation of the PGE2/PTGER2/PKA axis, facilitating entry into a PKA-dominant rather than AKT-dominant cellular state. We propose the use of PGE2 for in vitro decidualization as an alternative to 8-Br-cAMP.

Response to Rodgers: The hepatic glucose-mobilizing effect of glucagon is not mediated by cyclic AMP most of the time'

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