Oxytocin (OXT) and OXT receptor (OXTR) have been implicated in the regulation of energy homeostasis, but the detailed mechanism is still unclear. We recently showed late-onset obesity and impaired ...cold-induced thermogenesis in male OXTR knockout (Oxtr−/−) mice. Here we demonstrate that the OXTR in the hypothalamus has important functions in thermoregulation. Male Oxtr−/− mice failed to maintain their body temperatures during exposure to a cold environment. Oxtr−/− mice also showed decreased neuronal activation in the thermoregulatory hypothalamic region during cold exposure. Normal cold-induced thermogenesis was recovered in Oxtr−/− mice by restoring OXTR to the hypothalamus with an adeno-associated virus-Oxtr vector. In addition, brown adipose tissue (BAT) in Oxtr−/− mice contained larger lipid droplets in both 10- and 20-week-old compared with BAT from age-matched Oxtr+/+ control mice. In BAT, the expression level of β3-adrenergic receptor at normal temperature was lower in Oxtr−/− mice than that in control mice. In contrast, α2A-adrenergic receptor expression level was higher in BAT from Oxtr−/− mice in both normal and cold temperatures. Because β3- and α2A-adrenergic receptors are known to have opposite effects on the thermoregulation, the imbalance of adrenergic receptors is suspected to affect this dysfunction in the thermoregulation. Our study is the first to demonstrate that the central OXT/OXTR system plays important roles in the regulation of body temperature homeostasis.
Bortezomib is now widely used for the treatment of multiple myeloma (MM); however, its action mechanisms are not fully understood. Despite the initial results, recent investigations have indicated ...that bortezomib does not inactivate nuclear factor-κB activity in MM cells, suggesting the presence of other critical pathways leading to cytotoxicity. In this study, we show that histone deacetylases (HDACs) are critical targets of bortezomib, which specifically down-regulated the expression of class I HDACs (HDAC1, HDAC2, and HDAC3) in MM cell lines and primary MM cells at the transcriptional level, accompanied by reciprocal histone hyperacetylation. Transcriptional repression of HDACs was mediated by caspase-8–dependent degradation of Sp1 protein, the most potent transactivator of class I HDAC genes. Short-interfering RNA-mediated knockdown of HDAC1 enhanced bortezomib-induced apoptosis and histone hyperacetylation, whereas HDAC1 overexpression inhibited them. HDAC1 overexpression conferred resistance to bortezomib in MM cells, and administration of the HDAC inhibitor romidepsin restored sensitivity to bortezomib in HDAC1-overexpressing cells both in vitro and in vivo. These results suggest that bortezomib targets HDACs via distinct mechanisms from conventional HDAC inhibitors. Our findings provide a novel molecular basis and rationale for the use of bortezomib in MM treatment.
Mesenchymal stromal cells (MSCs) have unique characteristics such immune suppression by inhibiting T cell proliferation, tissue-repair ability and acceleration of hemopoietic stem cell engraftment. ...The cells are rare in bone marrow, but easily cultured under standard culture conditions. Soluble factors and cells are implicated in the MSC-mediated T cell suppression and numerous clinical trials using MSCs to prevent and treat graft-versus-host disease (GVHD) have been reported. MSCs are suggested to suppress acute GVHD without impairing graft-versus-leukemia effects and increasing systemic infections. In this review, we focus on basic aspects of MSC-mediated T cell suppression and clinical trials using MSCs for GVHD and related conditions.
The corticospinal (CS) tract emerged and evolved in mammals, and is essentially involved in voluntary movement. Over its phylogenesis, CS innervation gradually invaded to the ventral spinal cord, ...eventually making direct connections with spinal motoneurons (MNs) in higher primates. Despite its importance, our knowledge of the origin of the direct CS-MN connections is limited; in fact, there is controversy as to whether these connections occur in subprimate mammals, such as rodents. Here we studied the retrograde transsynaptic connection between cortical neurons and MNs in mice by labeling the cells with recombinant rabies virus. On postnatal day 14 (P14), we found that CS neurons make direct connections with cervical MNs innervating the forearm muscles. Direct connections were also detected electrophysiologically in whole cell recordings from identified MNs retrogradely-labeled from their target muscles and optogenetic CS stimulation. In contrast, few, if any, lumbar MNs innervating hindlimbs showed direct connections on P18. Moreover, the direct CS-MN connections observed on P14 were later eliminated. The transient CS-MN cells were distributed predominantly in the M1 and S1 areas. These findings provide insight into the ontogeny and phylogeny of the CS projection and appear to settle the controversy about direct CS-MN connections in subprimate mammals.
Adeno-associated virus (AAV) vectors are promising tools for gene therapy. The current AAV vector system produces an abundance of empty capsids that are eliminated before clinical use, leading to ...increased costs for gene therapy. In the present study, we established an AAV production system that regulates the timing of capsid expression using a tetracycline-dependent promoter. Tetracycline-regulating capsid expression increased viral yield and reduced empty capsids in various serotypes without altering AAV vector infectivity in vitro and in vivo. The replicase expression pattern change observed in the developed AAV vector system improved viral quantity and quality, whereas timing control of capsid expression reduced empty capsids. These findings provide a new perspective on the development of AAV vector production systems in gene therapy.
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•Novel AAV vector system controlling Cap expression timing (Tet-Cap) was established•Tet-Cap system was applicable for various serotypes in AAV vector production•Rep expression pattern change affected the AAV vector yield and quality•Controlling Cap expression timing mainly improved the AAV vector quality
Virology; Biotechnology
The DNA methylation inhibitor azacitidine (5-azacytidine) is used against myelodysplastic syndrome and acute myeloid leukemia, but drug resistance is an ongoing, intractable problem. To investigate ...resistance mechanisms, we generated two azacitidine-resistant cell lines, THP-1/AR and HL60/AR, and studied genetic disparities between them and their corresponding parental lines. In cells treated with azacitidine, significant mitotic variations were noted in parental cells which were absent in resistant cells, suggesting that resistance arises from negating azacitidine-mediated activation of apoptosis signaling and reestablishing G2 /M checkpoint. Importantly, both resistant cell lines have common point mutations in the uridine-cytidine kinase 2 ( UCK2 ) gene, which encodes the rate-limiting enzyme of the azacitidine activation pathway. Forced expression of mutated UCK2 in parental THP-1 cells abrogated azacitidine-induced apoptosis, whereas overexpression of wild type UCK2 in resistant THP-1/AR cells restored sensitivity to azacitidine, implying that UCK2 gene mutations perturb azacitidine activation and advance azacitidine resistance. Our study provides new insights into azacitidine resistance and establishes models useful in developing effective strategies to overcome it.
Data characterizing the safety and effectiveness of eculizumab in patients with paroxysmal nocturnal hemoglobinuria (PNH) are limited. We describe the safety and effectiveness of eculizumab in PNH ...patients enrolled in a post-marketing surveillance study. Types and frequencies of observed adverse events were similar to those reported in previous clinical trials and no meningococcal infection was reported. Effectiveness outcomes included the reduction of intravascular hemolysis, the change in hemoglobin (Hb) level, the withdrawal of transfusion and corticosteroids, the change of renal function, and overall survival. The effect of eculizumab on intravascular hemolysis was demonstrated by a reduction in lactate dehydrogenase levels at all measurements after baseline. Significant increases in Hb levels from baseline were also observed after 1 month’s treatment with eculizumab (
p
< 0.01). Of those who were transfusion-dependent at baseline, the median number of transfusions decreased significantly from 18 to 0 unit/year after 1 year of treatment with eculizumab (
p
< 0.001). An increase in Hb and a high rate of transfusion independence were observed, especially in patients with platelet count ≥150 × 10
9
/L. Approximately 97 % of patients showed maintenance or improvement of renal function. Overall survival rate was about 90 % (median follow-up 1.9 years). These results suggest an acceptable safety profile and favorable prognosis after eculizumab intervention.
Despite the increasing commercial use of nanoparticles, little is known about their effects on placental inflammation and pregnancy complications. In this study, nanosilica (NS) particles upregulated ...the inflammasome component nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) and induced placental inflammation and reactive oxygen species (ROS) generation, resulting in pregnancy complications. Furthermore, NS-induced pregnancy complications were markedly improved in Nlrp3
−/−
mice but not in component apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC)-deficient (Asc
−/−
) mice, indicating the independence of NLRP3 inflammasomes. Pregnancy complications in Nlrp3
−/−
and Asc
−/−
mice phenotypes were dependent on the balance between interleukin (IL)-1α and IL-10. NS-induced pregnancy complications were completely prevented by either inhibition of ROS generation or forced expression of IL-10. Our findings provide important information about NS-induced placental inflammation and pregnancy complications and the novel pathophysiological roles of NLRP3 and ASC in pregnancy.
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