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In addition to key roles in embryonic neurogenesis and myelinogenesis, γ-aminobutyric acid (GABA) serves as the primary inhibitory mammalian neurotransmitter. In yeast, we have identified a new role for GABA that augments activity of the pivotal kinase, Tor1. GABA inhibits the selective autophagy pathways, mitophagy and pexophagy, through Sch9, the homolog of the mammalian kinase, S6K1, leading to oxidative stress, all of which can be mitigated by the Tor1 inhibitor, rapamycin. To confirm these processes in mammals, we examined the succinic semialdehyde dehydrogenase (SSADH)-deficient mouse model that accumulates supraphysiological GABA in the central nervous system and other tissues. Mutant mice displayed increased mitochondrial numbers in the brain and liver, expected with a defect in mitophagy, and morphologically abnormal mitochondria. Administration of rapamycin to these mice reduced mTOR activity, reduced the elevated mitochondrial numbers, and normalized aberrant antioxidant levels. These results confirm a novel role for GABA in cell signaling and highlight potential pathomechanisms and treatments in various human pathologies, including SSADH deficiency, as well as other diseases characterized by elevated levels of GABA.

Objective. To evaluate the effects of He's Yangchao Recipe (HSYC) on ameliorating ovarian oxidative stress of aging mice under consecutive superovulation. Methods. An 8-month-old C57BL/6 female mouse was chosen to establish an aging model under ovarian hyperstimulation. Mice were randomly separated into four groups: R1 as the control group, R4 as the model group, NR4 with N-acetyl-L-cysteine (NAC) administration, and TR4 with HSYC administration. Oocyte collection, in vitro fertilization, and embryo culture were performed. The serum hormone levels were measured by enzyme-linked immunosorbent assays (ELISA); the reactive oxygen species (ROS) level of oocytes, the number of growing follicles, corpus luteum, ovulated oocytes, and developing embryos at each stage, along with the proportions of fragmented oocytes and abnormal mitochondria in granulosa cells (GCs) and the apoptosis rate of GCs were calculated; the mRNA and protein levels of JNK, P53, BAX were detected by real-time PCR and the Simple Western System. Results. HSYC enhanced estradiol, progesterone, and inhibin-B levels and increased growing follicle and corpus luteum and ovulated egg counts compared to the R4 group (P < 0.05), whereas it decreased the proportions of fragmented oocytes (P < 0.01); Meanwhile, embryos from mice subjected to four superovulation cycles with HSYC treated had a higher hatching potential. The ROS level of oocytes is downregulated by HSYC (P < 0.01) and the percentage of abnormal mitochondrial in ovaries of the TR4 group was also significantly declined compared to the R4 group (P < 0.05); the most TUNEL-positive cells proportion was detected in the R4 group; nevertheless, HSYC effectively attenuated this detrimental effect (P < 0.05). The mRNA and protein expressions of JNK and P53 in ovary tissues were reduced in the TR4 group while these genes were upregulated by repeated superovulation (P < 0.05). Conclusions. HSYC exerted promising effects on promoting the diminished ovarian reserve and decreased oocyte quality induced by both aging and consecutive ovarian superovulation, potentially via the ROS/JNK/p53 pathway. [ABSTRACT FROM AUTHOR]

Since the first isolation in 1943, the dengue virus (DENV) has spread throughout the world, but effective antiviral drugs or vaccines are still not available. To provide a more stable reporter DENV for vaccine development and antiviral drug screening, we constructed a reporter DENV containing the NanoLuc reporter gene, which was inserted into the 5′ untranslated region and capsid junction region, enabling rapid virus rescue by in vitro ligation. In addition, we established a live imaging mouse model and found that the reporter virus maintained the neurovirulence of prototype DENV before engineering. DENV-4 exhibited dramatically increased neurovirulence following a glycosylation site-defective mutation in the envelope protein. Significant mice mortality with neurological onset symptoms was observed after intracranial infection of wild-type (WT) mice, thus providing a visualization tool for DENV virulence assessment. Using this model, DENV was detected in the intestinal tissues of WT mice after infection, suggesting that intestinal lymphoid tissues play an essential role in DENV pathogenesis. [ABSTRACT FROM AUTHOR]

T cell factor 1 (Tcf1) is known as a critical mediator for natural killer (NK) cell development and terminal maturation. However, its essential targets and precise mechanisms involved in early NK progenitors (NKP) are not well clarified. To investigate the role of Tcf1 in NK cells at distinct developmental phases, we employed three kinds of genetic mouse models, namely, Tcf7 fl/fl Vav Cre/+, Tcf7 fl/fl CD122 Cre/+ and Tcf7 fl/fl Ncr1 Cre/+ mice, respectively. Similar to Tcf1 germline knockout mice, we found notably diminished cell number and defective development in BM NK cells from all strains. In contrast, Tcf7 fl/fl Ncr1 Cre/+ mice exhibited modest defects in splenic NK cells compared with those in the other two strains. By analyzing the published ATAC-seq and ChIP-seq data, we found that Tcf1 directly targeted 110 NK cell-related genes which displayed differential accessibility in the absence of Tcf1. Along with this clue, we further confirmed that a series of essential regulators were expressed aberrantly in distinct BM NK subsets with conditional ablating Tcf1 at NKP stage. Eomes , Ets1 , Gata3 , Ikzf1 , Ikzf2 , Nfil3 , Runx3 , Sh2d1a , Slamf6 , Tbx21 , Tox , and Zeb2 were downregulated, whereas Spi1 and Gzmb were upregulated in distinct NK subsets due to Tcf1 deficiency. The dysregulation of these genes jointly caused severe defects in NK cells lacking Tcf1. Thus, our study identified essential targets of Tcf1 in NK cells, providing new insights into Tcf1-dependent regulatory programs in step-wise governing NK cell development. [ABSTRACT FROM AUTHOR]

Aim of the Study. This study is aimed at exploring the effects and pharmacological mechanisms of the extracts from the Heritiera littoralis fruit (EFH) on dextran sulfate sodium- (DSS-) induced ulcerative colitis (UC) in mice. Materials and Methods. The chemical compositions of EFH were identified using LC-ESI-MS. The mice with 3% DSS-induced UC were administered EFH (200, 400, and 800 mg/kg), sulfasalazine (SASP, 200 mg/kg), and azathioprine (AZA, 13 mg/kg) for 10 days via daily gavage. The colonic inflammation was evaluated by the disease activity index (DAI), colonic length, histological scores, and levels of inflammatory mediators. The gut microbiota was characterized by 16S rRNA gene sequencing and analysis. Results. LC-ESI-MS analysis showed that EFH was rich in alkaloids and flavones. The results indicated that EFH significantly improved the DAI score, relieved colon shortening, and repaired pathological colonic variations in colitis. In addition, proteins in the NF-κB pathway were significantly inhibited by EFH. Furthermore, EFH recovered the diversity and balance of the gut microbiota. Conclusions. EFH has protective effects against DSS-induced colitis by keeping the balance of the gut microbiota and suppressing the NF-κB pathway. [ABSTRACT FROM AUTHOR]

Background: Although ClC-2 channels are important in colonic Cl- secretion, it is unclear about their roles in small intestinal anion secretion. Therefore, we sought to examine whether ClC-2 channels play important roles in anion secretion, particularly duodenal bicarbonate secretion (DBS).Methods: Duodenal mucosae from mice were stripped of seromuscular layers and mounted in Ussing chambers. Both duodenal short-circuit current (Isc) and HCO3- secretion in vitro were simultaneously recorded. DBS in vivo was measured by a CO2-sensitive electrode.Results: Lubiprostone, a selective ClC-2 activator, concentration-dependently increased both duodenal Isc and DBS only when applied basolaterally, but not when applied apically. Removal of extracellular Cl- abolished lubiprostone-induced duodenal Isc, but did not alter HCO3- secretion even in the presence of DIDS, a Cl-/HCO3- exchanger inhibitor. However, further addition of glibenclamide, a CFTR channel blocker, abolished lubiprostone-evoked HCO3- secretion. Moreover, lubiprostone-induced HCO3- secretion was impaired in CFTR-/- mice compared to wild-type littermates. Luminal perfusion of duodenal lumen with lubiprostone did not alter basal DBS in vivo, but lubiprostone (i.p.) was able to induce DBS, which was also significantly inhibited by Cd2+, a ClC-2 channel blocker. [Ca2+]cyt level, Ca2+-activated K+ channel- and cAMP-mediated duodenal Isc, and HCO3- secretion were unchanged by lubiprostone.Conclusions: We have provided the first evidence for the novel functional role of basolateral ClC-2 channels in the regulation of duodenal anion secretion. [ABSTRACT FROM AUTHOR]

Acute liver injury is a common consequence of taking overdose of acetaminophen (APAP). The aim of this study was to evaluate the antioxidant activity and hepatoprotective effect of a mangrove plant Sonneratia apetala fruit extract (SAFE) on APAP-induced liver injury in mice. Mice were orally pretreated with SAFE (100, 200, and 400 mg/kg) daily for one week. The control and APAP groups were intragastrically administered with distilled water, and NAC group was treated with N-Acetyl-L-cysteine (NAC) before APAP exposure. The results manifested that SAFE significantly improved survival rates, attenuated hepatic histological damage, and decreased the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in serum in APAP-exposed mice. SAFE treatment also increased glutathione (GSH) level and glutathione peroxidase (GSH-Px) activity, enhanced catalase (CAT), and total antioxidant capacity (T-AOC), as well as reducing malondialdehyde (MDA) level in liver. In addition, the formation of tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and elevation of myeloperoxidase (MPO) in APAP-exposed mice were inhibited after SAFE treatment. And SAFE also displayed high DPPH radical scavenging activity and reducing power in vitro. The main bioactive components of SAFE such as total phenol, flavonoid, condensed tannin, and carbohydrate were determined. The current study proved that SAFE exerted potential protective effect against APAP-induced acute liver injury, which might be associated with the antioxidant and anti-inflammatory activities of SAFE. [ABSTRACT FROM AUTHOR]

Submicron phase-change droplets are an emerging class of ultrasound contrast agent. Compared with microbubbles, their relatively small size and increased stability offer the potential to passively extravasate and accumulate in solid tumors through the enhanced permeability and retention effect. Under exposure to sufficiently powerful ultrasound, these droplets can convert into in situ gas microbubbles and thus be used as an extravascular-specific contrast agent. However, in vivo imaging methods to detect extravasated droplets have yet to be established. Here, we develop an ultrasound imaging pulse sequence within diagnostic safety limits to selectively detect droplet extravasation in tumors. Tumor-bearing mice were injected with submicron perfluorobutane droplets and interrogated with our imaging-vaporization-imaging sequence. By use of a pulse subtraction method, median droplet extravasation signal relative to the total signal within the tumor was estimated to be Etumor=37±5% compared with the kidney Ekidney=-2±8% (p < 0.001). This work contributes toward the advancement of volatile phase-shift droplets as a next-generation ultrasound agent for imaging and therapy. [ABSTRACT FROM AUTHOR]

Chinese herbal medicine Gegen Qinlian Decoction (GQD) has been clinically shown to be an effective treatment of ulcerative colitis (UC) in China. However, the underlying mechanism of GQD's anti-ulcerative colitis properties and its effect on gut microbiota still deserve further exploration. This study observed the regulatory effects of GQD on Th2/Th1 and Tregs/Th17 cells balance, the NOD-like receptor family pyrin domain containing 3 (NLRP3) infammasome and gut microbiota in TNBS-induced UC in BALB/c mice. 61 main chemical compounds in the GQD were determined by UPLC-Q-TOF/MS. The UC BALB/c model was established by intrarectal administration of trinitrobenzene sulfonic acid (TNBS), and GQD was orally administered at low and high dosages of 2.96 and 11.83 g/kg/day, respectively. The anti-inflammatory effects of GQD for ulcerative colitis were evaluated by survival rate, body weight, disease activity index (DAI) score, colonic weight and index, spleen index, hematoxylin-eosin (HE) staining and histopathological scores. Flow cytometry was used to detect the percentage of CD4, Th1, Th2, Th17 and Tregs cells. The levels of Th1-/Th2-/Th17-/Tregs-related inflammatory cytokines and additional proinflammatory cytokines (IL-1β, IL-18) were detected by CBA, ELISA, and RT-PCR. The expressions of GATA3, T-bet, NLRP3, Caspase-1, IL-Iβ, Occludin and Zonula occludens-1 (ZO-1) on colon tissues were detected by Western blot and RT-PCR. Transcriptome sequencing was performed using colon tissue and 16S rRNA gene sequencing was performed on intestinal contents. Fecal microbiota transplantation (FMT) was employed to assess the contribution of intestinal microbiota and its correlation with CD4 T cells and the NLRP3 inflammasome. GQD increased the survival rate of TNBS-induced UC in BALB/c mice, and significantly improved their body weight, DAI score, colonic weight and index, spleen index, and histological characteristics. The intestinal barrier dysfunction was repaired after GQD administration through promoting the expression of tight junction proteins (Occludin and ZO-1). GQD restored the balance of Th2/Th1 and Tregs/Th17 cells immune response of colitis mice, primarily inhibiting the increase in Th2/Th1 ratio and their transcription factor production (GATA3 and T-bet). Morever, GQD changed the secretion of Th1-/Th2-/Th17-/Tregs-related cytokines (IL-2, IL-12, IL-5, IL-13, IL-6, IL-10, and IL-17A) and reduced the expressions of IL-1β, IL-18. Transcriptome results suggested that GQD could also remodel the immune inflammatory response of colitis by inhibiting NOD-like receptor signaling pathway, and Western blot, immunohistochemistry and RT-PCR further revealed that GQD exerted anti-inflammatory effects by inhibiting the NLRP3 inflammasome, such as down-regulating the expression of NLRP3, Caspase-1 and IL-1β. More interestingly, GQD regulated gut microbiota dysbiosis, suppressed the overgrowth of conditional pathogenic gut bacteria like Helicobacter, Proteobacteria, and Mucispirillum, while the probiotic gut microbiota, such as Lactobacillus, Muribaculaceae, Ruminiclostridium_6, Akkermansia, and Ruminococcaceae_unclassified were increased. We further confirmed that GQD-treated gut microbiota was sufficient to relieve TNBS-induced colitis by FMT, involving the modulation of Th2/Th1 and Tregs/Th17 balance, inhibition of NLRP3 inflammasome activation, and enhancement of colonic barrier function. GQD might alleviate TNBS-induced UC via regulating Th2/Th1 and Tregs/Th17 cells Balance, inhibiting NLRP3 inflammasome and reshaping gut microbiota, which may provide a novel strategy for patients with colitis. The graph created by Figdraw (https://www.figdraw.com). The caption of the abstract graphic: The major components of GQD was verified by UPLC-Q-TOF/MS. Based on molecular docking and transcriptome sequencing, GQD could relieve UC symptoms by modulating Th2/Th1 and Tregs/Th17 cells Balance, inhibiting NLRP3 inflammasome activation. Besides, GQD reshaped gut microbiota and improved intestinal barrier dysfunction. [Display omitted] • Gegen Qinlian Decoction (GQD) alleviated TNBS-induced UC in BALB/c mice. • GQD regulated the balance of CD4 T subsets (Th2/Th1 and Tregs/Th17 cells), mainly suppress-ing the increase of Th2 and Th1 ratio. • GQD inhibited the activation of NLRP3 inflammasome. • GQD reshaped the gut microbiota and repaired the dysfunction of the intestinal barrier. [ABSTRACT FROM AUTHOR]

Abstract: Lipopolysaccharide (LPS) plays an important role in Gram-negative bacteria-induced sepsis and multiple organ dysfunction syndrome, which are still the leading cause of high mortality in intensive care units. Although paeoniflorin (Pae) has reportedly exhibited anti-inflammatory effect and protection against immunological liver injury in mice, it is not known whether Pae improve survival in endotoxemic mice. The purpose of this study was to determine the effect of Pae on the mortality, multiple organ dysfunction and cytokine production in lipopolysaccharide (LPS)-treated mice. We found that pretreatment with Pae decreased mortality, reduced lung and kidney injury, decreased serum creatinine level and improve systolic function of heart in mice challenged with LPS. Further experiments showed that Pae inhibited LPS-stimulated tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) release and promoted LPS-induced interleukin-10 (IL-10) production. Our results indicate that Pae protects mice against lethal LPS challenge, at least in part, through inhibiting TNF-α and IL-1β production and accelerating IL-10 expression. [ABSTRACT FROM AUTHOR]

Vitiligo is a common depigmentary disease characterized as diagnosis simplicity and cure difficulty in view of the ambiguity of etiology, thus novel and effective treatments are urgently needed. Paeoniflorin, the major active compound extracted from the root of Paeonia lactiflora Pall , a traditional Chinese medicine, has been validated pharmacological properties such as antioxidant stress, a theory participating in the occurrence of vitiligo, but the effect on melanogenesis is still unclear. In this study, melanosythesis effect of paeoniflorin and the potential mechanism were evaluated. We found that treatment with paeoniflorin at the concentration of 10 μg/ml significantly increased melanin content and intracellular tyrosinase activity of human melanocytes, in accordance with the elevation of protein levels of microphthalmia-associated transcription factor (MITF), tyrosinase-related protein 1 (TRP-1). In addition, we also investigated that paeoniflorin promoted phosphorylation of cAMP-response element binding (CREB) and extracellular signal-regulated kinase (ERK) without affecting p38 and c-Jun N-terminal kinase (JNK). These results demonstrated that paeoniflorin had a synergistic effect on normal human melanocytes via ERK/CREB pathway with up-regulation of MITF and TRP-1, enhancing melanin synthesis. Meanwhile, the milder pathological changes in vitiligo mice treat with paeoniflorin also confirmed its potential in treating vitiligo. To sum up, we suggest that paeoniflorin may be a potential medicine of vitiligo treatment in clinical. Unlabelled Image [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is characterized by high vascularity, but anti-angiogenic therapies show poor efficacy. Centromere protein U (CENPU), a centromere component essential for mitosis, is associated with tumorigenesis in multiple cancers; however, little is known of its role in breast cancer. Here, we investigate its expression and function of promoting angiogenesis in TNBC. Immunohistochemical staining revealed high CENPU expression in TNBC tissue and high CENPU levels correlated significantly with poor distant metastasis-free and overall survival. Knockdown of CENPU in TNBC cells inhibited vascular endothelial growth factor A (VEGFA) production and significantly reduced tube formation and migration of human umbilical vein endothelial cells in vitro. In a mouse xenograft model, CENPU knockdown reduced TNBC tumor growth concomitant with a reduction in CD31 + microvessel density. Mechanistic studies revealed that CENPU promoted angiogenesis by inhibiting the ubiquitination and proteasomal degradation of cyclooxygenase-2 (COX-2), leading to increased activation of the COX-2-p-ERK-HIF-1α-VEGFA signaling pathway. Taken together, our results demonstrate a critical role for CENPU in COX-2-mediated signaling for angiogenesis, and identify a role of CENPU in regulating angiogenesis in TNBC. [ABSTRACT FROM AUTHOR]

• 2'-AA exhibited significant anti-osteoporotic effects on ovariectomized mice. • 2'-AA improved bone micro-architecture without the proliferation of uterine tissue. • 2'-AA could prevent bone resorption rather than stimulate bone formation on OVX mice. • Micro-CT and three-point bending test intuitively observed the beneficial effect. • The mechanisms related to RANKL/RANK/TRAF6 mediated NF-κB/NFATc1 pathway. 2'-Acetylacteoside-(2'-AA), a bioactive constituent isolated from Cistanche deserticola , has been proven to possess a variety of important pharmacological effects, thus brought an increased amount of scientists' attention. As the extract of C. deserticola exhibited significant anti-osteoporotic bioactivity in our previous study, we proposed that 2'-AA maybe one of the responsibilities. As a result, 2'-AA (10, 20 and 40 mg/kg body weight/day) exhibited significant anti-osteoporotic effects on ovariectomized (OVX) mice after 12 weeks of oral administration, confirmed by the increased bone mineral density, enhanced bone strength and improved trabecular bone micro-architecture including bone mineral content, tissue mineral content, trabecular number, and trabecular separation of OVX mice. Moreover, the properties of bone resorption markers including cathepsin K, TRAP and deoxypyridinoline were significantly suppressed, whereas the activities of bone formation index like ALP and BGP as well as the weights of the body, uterus, and vagina were seemingly not influenced by 2'-AA intervention. Mechanistically, the above therapeutic effect of 2'-AA on bone resorption of OVX mice operated maybe mainly through RANKL/RANK/TRAF6-mediated NF-κB/NFATc1 pathway, which was confirmed by the down-regulated expressions of RANK, TRAF6, IκB kinase β, NF-κB and NFATc1. Summarily, 2'-AA exhibited significant anti-osteoporotic activity and may be regarded as a promising anti-osteoporotic candidate for future clinical trial. [ABSTRACT FROM AUTHOR]