The specification of left-right asymmetry of the visceral organs is precisely regulated. The earliest breakage of left-right symmetry occurs as the result of leftward flow generated by asymmetric beating of nodal cilia, which eventually induces asymmetric Nodal/Lefty/Pitx2 expression on the left side of the lateral plate mesoderm. PIERCE1 has been identified as a p53 target gene involved in the DNA damage response. In this study, we found that Pierce1-null mice exhibit severe laterality defects, including situs inversus totalis and heterotaxy with randomized situs and left and right isomerisms. The spectrum of laterality defects was closely correlated with randomized expression of Nodal and its downstream genes, Lefty1/2 and Pitx2. The phenotype of Pierce1-null mice most closely resembled that of mutant mice with impaired ciliogenesis and/or ciliary motility of the node. We also found the loss of asymmetric expression of Cerl2, the earliest flow-responding gene in the node of Pierce1-null embryos. The results suggest that Pierce1-null embryos have defects in generating a symmetry breaking signal including leftward nodal flow. This is the first report implicating a role for PIERCE1 in the symmetry-breaking step of left-right asymmetry specification.

Non-alcoholic fatty liver disease (NAFLD) results from triglyceride accumulation within the liver and some of them advances to non-alcoholic steatohepatitis (NASH). It is important to note that in NAFLD development, hepatic de novo lipogenesis (DNL) derives from excess carbohydrates and fats under a condition of excess energy through β-oxidation. As a main regulator for DNL, sterol regulatory element-binding protein 1 (Srebp-1) forms complex with progesterone receptor membrane component 1 (Pgrmc1). To investigate whether Pgrmc1 may have a notable effect on DNL via SREBP-1 activation, we generated Pgrmc1 knockout (KO) mice and fed a high fat diet for one month. High-fat-fed Pgrmc1 KO mice showed a substantial increase in levels of hepatic TG accumulation, and they were predisposed to NAFLD when compared to WT mice. Loss of Pgrmc1 increased mature SREBP-1 protein level, suggesting that induction of hepatic steatosis in Pgrmc1 KO mice might be triggered by de novo lipogenesis. Moreover, Pgrmc1 KO mice were also more vulnerable to early stage of NASH, showing high levels of alanine aminotransferase, obesity-linked pro-inflammatory cytokines, and fibrosis markers. This is interesting because Pgrmc1 involves with the first step in regulating the hepatic de novo lipogenesis under an excess energy condition.

Symbionts play an indispensable role in gut homeostasis, but underlying mechanisms remain elusive. To clarify the role of lactic-acid-producing bacteria (LAB) on intestinal stem-cell (ISC)-mediated epithelial development, we fed mice with LAB-type symbionts such as Bifidobacterium and Lactobacillus spp. Here we show that administration of LAB-type symbionts significantly increased expansion of ISCs, Paneth cells, and goblet cells. Lactate stimulated ISC proliferation through Wnt/β-catenin signals of Paneth cells and intestinal stromal cells. Moreover, Lactobacillus plantarum strains lacking lactate dehydrogenase activity, which are deficient in lactate production, elicited less ISC proliferation. Pre-treatment with LAB-type symbionts or lactate protected mice in response to gut injury provoked by combined treatments with radiation and a chemotherapy drug. Impaired ISC-mediated epithelial development was found in mice deficient of the lactate G-protein-coupled receptor, Gpr81. Our results demonstrate that LAB-type symbiont-derived lactate plays a pivotal role in promoting ISC-mediated epithelial development in a Gpr81-dependent manner.

Prenatal exposure to alcohol promotes the level of reactive oxygen species within embryos and results in developmental disorders. In this study, we investigated the effect of capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide), the major pungent ingredient in red peppers, on ethanol-induced teratogenicity in mouse embryos (embryonic days 8.5-10.5). In response to ethanol administration (1.0 microl/ml), developmental parameters such as yolk sac circulation, allantois, heart, hindbrain, midbrain, forebrain, otic and optic systems, branchial bar, olfactory system, forelimb, hindlimb, and somites decreased significantly in comparison with those of control group (p<0.05). However, the concurrent administration of capsaicin (1 x 10(-8) microg/ml or 1 x 10(-7) microg/ml) and ethanol significantly ameliorated most of the morphological scores excepting yolk sac circulation and hindlimb scores (p<0.05). Furthermore, the levels of superoxide dismutase activity and cytoplasmic glutathione peroxidase and phospholipid hydroperoxide glutathione peroxidase mRNAs in the ethanol-treated embryos recovered to the levels observed in control embryos by capsaicin co-administration. These results indicate that capsaicin has a protective effect against ethanol-induced teratogenicity via an antioxidative activity.

Hepatic gluconeogenesis is the main pathway for blood glucose maintenance activated during fasting. Retardation of insulin action, such as in diabetes mellitus, activates gluconeogenesis during the fed state. While the role of progesterone (P4) in diabetes is controversial, the P4 receptor, progesterone receptor membrane component 1 (PGRMC1), is known to stimulate pancreatic insulin secretion. We investigated the role of P4, via hepatic PGRMC1, during gluconeogenesis. The PGRMC1 binding chemical, AG-205, induced PGRMC1 monomer (25 kDa) abundance, and increased PEPCK expression and glucose production in parallel with cyclic AMP (cAMP) induction in Hep3B cells. PGRMC1-mediated cyclic AMP was inhibited by an adenylate cyclase inhibitor (MDL-12,330A). PEPCK suppression in Pgrmc1 KO hepatocyte was not observed after treatment of MDL-12,330A. PGRMC1 knockdown or overexpression systems in Hep3B cells confirmed that PGRMC1 mediates PEPCK expression via phosphorylation of cAMP-response element binding protein (CREB). CREB phosphorylation and PEPCK expression in primary hepatocytes were greater than that in PGRMC1 knock-out hepatocytes. Progesterone increased PGRMC1 expression, which induced cAMP and PEPCK induction and glucose production. In vivo, P4 suppressed gluconeogenesis following plasma insulin induction under normal conditions in a mouse model. However, P4 increased blood glucose via gluconeogenesis in parallel with increases in PGRMC1 and PEPCK expression in mice in both insulin-deficient and insulin-resistant conditions. We conclude that P4 increases hepatic glucose production via PGRMC1, which may exacerbate hyperglycaemia in diabetes where insulin action is limited.

Identification of a new agent from natural products for the protection of embryonic anomalies is potentially valuable. To investigate the protective effect exerted by lycopene against nicotine-induced malformations, mouse embryos in embryonic day 8.5 with yolk sac placentas were cocultured with 1 mM nicotine and/or lycopene (1 × 10-6, 1 × 10-5 μM) for 48 h. The morphological defects and apoptotic cell deaths in the embryo and yolk sac placenta of the nicotine group were significantly increased. Exposure to nicotine resulted in reduced superoxide dismutase (SOD) activity and cytoplasmic SOD and cytoplasmic glutathione peroxidase mRNA levels, but increased lipid peroxidation level in embryos. Moreover, treatment with nicotine resulted in aggravated expressions of the mRNA or protein level of antiapoptotic (BCL2-associated X protein, B-cell lymphoma-extralarge, and caspase 3), anti-inflammatory (nuclear factor kappa-light-chain-enhancer of activated B cells and tumor necrosis factor-alpha), and vasculogenic (vascular endothelial growth factor-alpha, insulin-like growth factor-1, alpha smooth muscle actin, transforming growth factor-beta 1, and hypoxia inducible factor-1 alpha) factors in the embryo and yolk sac placenta. However, all the parameters were significantly improved by treatment with lycopene, as compared to the nicotine group. These findings indicate the potential of lycopene as a protective agent against embryonic anomalies and yolk sac vasculogenic and placenta-forming defects induced by nicotine through modulations of oxidative, apoptotic, vasculogenic, and inflammatory activities.

Although rats with melanin-pigmentated retinal pigment epithelial (RPE) cells are physiologically more appropriate models for human eye research than their albino counterparts, reliable models from the former strain are not available to study retinal degeneration. Here, we describe the development of a novel Pde6b-knockout Long-Evans (LE Pde6b KO) rat model that recapitulates key features of human retinitis pigmentosa (RP). After the generation of the Pde6b-knockout Sprague-Dawley rats with the CRISPR-Cpf1 system, the LE rat was back-crossed over 5 generations to develop the pigmented LE Pde6b KO strain. Interestingly, LE Pde6b KO displayed well-developed bone-spicule pigmentation; a hallmark of fundus in patients with RP which cannot be observed in non-pigmented albino rats. Moreover, the rat model showed progressive thinning of the retina, which was evident by intravital imaging with optical coherence tomography. Histologically, significant atrophy was observed in the outer nuclear layer. Functionally, LE Pde6b KO presented a marked decrease of amplitude level during electroretinogram testing, demonstrating significant loss of visual function. Therefore, these findings suggest that the LE Pde6b KO model robustly recapitulates the hallmark phenotype of RP. We believe that the LE Pde6b KO model may be used effectively for preclinical translational research to further study retinal degeneration.

Sphingosine 1-phosphate receptors (S1PRs) are a group of G-protein-coupled receptors that confer a broad range of functional effects in chronic inflammatory and metabolic diseases. S1PRs also may mediate the development of nonalcoholic steatohepatitis (NASH), but the specific subtypes involved and the mechanism of action are unclear.

Alcohol-associated liver disease (ALD) is caused by excessive abuse of alcohol. One of the most representative causes of ALD is the action of acetaldehyde. Acetaldehyde is a toxic material produced when alcohol is metabolized through some enzymes, and it causes endoplasmic reticulum (ER) stress, mitochondrial dysfunction, and tissue injury. In this study, we assessed the relationship between Progesterone receptor membrane component 1 (PGRMC1) and ALD because PGRMC1 is expressed in the ER and mitochondria in the liver. Using the chronic and binge alcohol feeding models, we assessed acetaldehyde level, liver damage, alcohol-degrading enzymes, and ER stress. Compared with wild-type (WT) mice ethanol-fed Pgrmc1 knockout (KO) mice had higher levels of alanine aminotransferase (ALT) and alcohol-degrading enzymes, and Pgrmc1 KO mice had high serum acetaldehyde and ER stress levels compared with WT mice with control and ethanol feeding. Loss of Pgrmc1 increased acetaldehyde production through increased expression of alcohol dehydrogenase and catalase, which led to increased ER stress and suggested that cell death was promoted. In conclusion, it has been proposed that the loss of PGRMC1 could promote ALD and cause liver damage in alcohol-abusing humans.NEW & NOTEWORTHY Loss of Pgrmc1 increased acetaldehyde production, and excess acetaldehyde consequently increased ER stress, which activates apoptosis. Since low expression of PGRMC1 is vulnerable to alcoholic liver damage, the loss of PGRMC1 expression may increase susceptibility to ALD.

Type I interferon (IFN-I) plays a critical role in the antitumor immune response. In our previous study, we showed that IFN-I-inducible 2'-5' oligoadenylate synthetase-like 1 (OASL1) negatively regulated IFN-I production upon tumor challenge similar to that of viral infection. Thus, OASL1-deficient (Oasl1 -/-) mice were more resistant to implanted tumor growth than wild-type (WT) mice. In this study, we investigated whether targeting or suppressing OASL1 could show synergistic effects on tumor clearance with conventional cancer therapies (such as chemotherapy and radiotherapy) using Oasl1 -/- mice and a transplantable lung metastatic tumor cell model. Upon treatment with the anticancer drug cisplatin, we found that Oasl1 -/- mice showed enhanced resistance to injected tumors compared to untreated Oasl1 -/- mice. Similarly, irradiated Oasl1 -/- mice showed better resistance to tumor challenge than untreated Oasl1 -/- mice. Additionally, we found that Oasl1 -/- mice applied with both types of the cancer therapies contained more cytotoxic effector cells, such as CD8+ T cells and NK cells, and produced more cytotoxic effector cytokine IFN-γ as well as IFN-I in their tumor-containing lungs compared to untreated Oasl1 -/- mice. Collectively, these results show that targeting OASL1 together with conventional cancer therapies could be an effective strategy to enhance treatment efficacy.

The rat is a time-honored traditional experimental model animal, but its use is limited due to the difficulty of genetic modification. Although engineered endonucleases enable us to manipulate the rat genome, it is not known whether the newly identified endonuclease Cpf1 system is applicable to rats. Here we report the first application of CRISPR-Cpf1 in rats and investigate whether Apoe knockout rat can be used as an atherosclerosis model. We generated Apoe- and/or Ldlr-deficient rats via CRISPR-Cpf1 system, characterized by high efficiency, successful germline transmission, multiple gene targeting capacity, and minimal off-target effect. The resulting Apoe knockout rats displayed hyperlipidemia and aortic lesions. In partially ligated carotid arteries of rats and mice fed with high-fat diet, in contrast to Apoe knockout mice showing atherosclerotic lesions, Apoe knockout rats showed only adventitial immune infiltrates comprising T lymphocytes and mainly macrophages with no plaque. In addition, adventitial macrophage progenitor cells (AMPCs) were more abundant in Apoe knockout rats than in mice. Our data suggest that the Cpf1 system can target single or multiple genes efficiently and specifically in rats with genetic heritability and that Apoe knockout rats may help understand initial-stage atherosclerosis.

Because anaplastic lymphoma kinase (ALK) is dependent on Hsp90 for protein stability, Hsp90 inhibitors are effective in controlling growth of lung cancer cells with ALK rearrangement. We investigated the mechanism of acquired resistance to 17-(Dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG), a geldanamycin analogue Hsp90 inhibitor, in H3122 and H2228 non-small cell lung cancer cell lines with ALK rearrangement.

Oxidative stress is a key mediator of neuronal death in acute brain injuries, such as epilepsy, trauma, and stroke. Although it is accompanied by diverse cellular changes, increases in levels of intracellular zinc ion (Zn2+) and calcium ion (Ca2+) may play a critical causative role in oxidative neuronal death. However, the mechanistic link between Zn2+ and Ca2+ dyshomeostasis in neurons during oxidative stress is not well-understood. Here, we show that the exposure of cortical neurons to H2O2 led to a zinc-triggered calcium influx, which resulted in neuronal death. The cyclin-dependent kinase inhibitor, NU6027, inhibited H2O2-induced Ca2+ increases and subsequent cell death in cortical neurons, without affecting the early increase in Zn2+. Therefore, we attempted to identify the zinc-regulated Ca2+ pathway that was inhibited by NU6027. The expression profile in cortical neurons identified transient receptor potential cation channel 5 (TRPC5) as a candidate that is known to involve in the generation of epileptiform burst firing and epileptic neuronal death (Phelan KD et al. 2012a; Phelan KD et al. 2013b). NU6027 inhibited basal and zinc-augmented TRPC5 currents in TRPC5-overexpressing HEK293 cells. Consistently, cortical neurons from TRPC5 knockout mice were highly resistant to H2O2-induced death. Moreover, NU6027 is neuroprotective in kainate-treated epileptic rats. Our results demonstrate that TRPC5 is a novel therapeutic target against oxidative neuronal injury in prolonged seizures and that NU6027 is a potent inhibitor of TRPC5.

Phenotypic analysis of gene-specific knockout (KO) mice has revolutionized our understanding of in vivo gene functions. As the use of mouse embryonic stem (ES) cells is inevitable for conventional gene targeting, the generation of knockout mice remains a very time-consuming and expensive process. To accelerate the large-scale production and phenotype analyses of KO mice, international efforts have organized global consortia such as the International Knockout Mouse Consortium (IKMC) and International Mouse Phenotype Consortium (IMPC), and they are persistently expanding the KO mouse catalogue that is publicly available for the researches studying specific genes of interests in vivo. However, new technologies, adopting zinc-finger nucleases (ZFNs) or Transcription Activator-Like Effector (TALE) Nucleases (TALENs) to edit the mouse genome, are now emerging as valuable and effective shortcuts alternative for the conventional gene targeting using ES cells. Here, we introduce the recent achievement of IKMC, and evaluate the significance of ZFN/TALEN technology in mouse genetics.

Here, in Ppara-/- mice, we found that an increased DNL stimulated the cartilage degradation and identified ACOT12 as a key regulatory factor. Suppressed level of ACOT12 was observed in cartilages of OA patient and OA-induced animal. To determine the role and association of ACOT12 in the OA pathogenesis, we generated Acot12 knockout (KO) (Acot12-/-) mice using RNA-guided endonuclease. Acot12-/- mice displayed the severe cartilage degradation with the stimulation of matrix MMPs and chondrocyte apoptosis through the accumulation of acetyl CoA. Delivery of acetyl CoA-conjugated chitosan complex into cartilage stimulated DNL and cartilage degradation. Moreover, restoration of ACOT12 into human OA chondrocytes and OA-induced mouse cartilage effectively rescued the pathophysiological features of OA by regulating DNL. Taken together, our study suggested ACOT12 as a novel regulatory factor in maintaining cartilage homeostasis and targeting ACOT12 could contribute to developing a new therapeutic strategy for OA.

In this study, we hypothesized that deregulation in the maintenance of the pool of coenzyme A (CoA) may play a crucial role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Specific deletion of Acot12 (Acot12-/-), the major acyl-CoA thioesterase, induced the accumulation of acetyl-CoA and resulted in the stimulation of de novo lipogenesis (DNL) and cholesterol biosynthesis in the liver. KEGG pathway analysis suggested PPARα signaling as the most significantly enriched pathway in Acot12-/- livers. Surprisingly, the exposure of Acot12-/- hepatocytes to fenofibrate significantly increased the accumulation of acetyl-CoA and resulted in the stimulation of cholesterol biosynthesis and DNL. Interaction analysis, including proximity-dependent biotin identification (BioID) analysis, suggested that ACOT12 may directly interact with vacuolar protein sorting-associated protein 33A (VPS33A) and play a role in vesicle-mediated cholesterol trafficking and the process of lysosomal degradation of cholesterol in hepatocytes. In summary, in this study, we found that ACOT12 deficiency is responsible for the pathogenesis of NAFLD through the accumulation of acetyl-CoA and the stimulation of DNL and cholesterol via activation of PPARα and inhibition of cholesterol trafficking.

Proper placental development in early pregnancy ensures a positive outcome later on. The developmental relationship between the placenta and embryonic organs, such as the heart, is crucial for a normal pregnancy. However, the mechanism through which the placenta influences the development of embryonic organs remains unclear. Trophoblasts fuse to form multinucleated syncytiotrophoblasts (SynT), which primarily make up the placental materno-fetal interface. We discovered that endogenous progesterone immunomodulatory binding factor 1 (PIBF1) is vital for trophoblast differentiation and fusion into SynT in humans and mice. PIBF1 facilitates communication between SynT and adjacent vascular cells, promoting vascular network development in the primary placenta. This process affected the early development of the embryonic cardiovascular system in mice. Moreover, in vitro experiments showed that PIBF1 promotes the development of cardiovascular characteristics in heart organoids. Our findings show how SynTs organize the barrier and imply their possible roles in supporting embryogenesis, including cardiovascular development. SynT-derived factors and SynT within the placenta may play critical roles in ensuring proper organogenesis of other organs in the embryo.

Studies have suggested that dysregulation of peroxisomal lipid metabolism might play an important role in colorectal cancer (CRC) development. Here, we found that KrasG12D-driven CRC tumors demonstrate dysfunctional peroxisomal b-oxidation and identified Nudt7 (peroxisomal coenzyme A diphosphatase NUDT7) as one of responsible peroxisomal genes. In KrasG12D-driven CRC tumors, the expression level of Nudt7 was significantly decreased. Treatment of azoxymethane/dextran sulfate sodium (AOM/DSS) into Nudt7 knockout (Nudt7-/-) mice significantly induced lipid accumulation and the expression levels of CRC-related genes whereas xenografting of Nudt7-overexpressed LS-174T cells into mice significantly reduced lipid accumulation and the expression levels of CRC-related genes. Ingenuity pathway analysis of microarray using the colon of Nudt7-/- and Nudt7+/+ mice treated with AOM/DSS suggested Wnt signaling as one of activated signaling pathways in Nudt7-/- colons. Upregulated levels of β-catenin were observed in the colons of KrasG12D and AOM/DSS-treated Nudt7-/- mice and downstream targets of β-catenin such as Myc, Ccdn1, and Nos2, were also significantly increased in the colon of Nudt7-/- mice. We observed an increased level of palmitic acid in the colon of Nudt7-/- mice and attachment of palmitic acid-conjugated chitosan patch into the colon of mice induced the expression levels of b-catenin and CRC-related genes. Overall, our data reveal a novel role for peroxisomal NUDT7 in KrasG12D-driven CRC development.

Although macroautophagy/autophagy deficiency causes degenerative diseases, the deletion of essential autophagy genes in adipocytes paradoxically reduces body weight. Brown adipose tissue (BAT) plays an important role in body weight regulation and metabolic control. However, the key cellular mechanisms that maintain BAT function remain poorly understood. in this study, we showed that global or brown adipocyte-specific deletion of pink1, a Parkinson disease-related gene involved in selective mitochondrial autophagy (mitophagy), induced BAT dysfunction, and obesity-prone type in mice. Defective mitochondrial function is among the upstream signals that activate the NLRP3 inflammasome. NLRP3 was induced in brown adipocyte precursors (BAPs) from pink1 knockout (KO) mice. Unexpectedly, NLRP3 induction did not induce canonical inflammasome activity. Instead, NLRP3 induction led to the differentiation of pink1 KO BAPs into white-like adipocytes by increasing the expression of white adipocyte-specific genes and repressing the expression of brown adipocyte-specific genes. nlrp3 deletion in pink1 knockout mice reversed BAT dysfunction. Conversely, adipose tissue-specific atg7 KO mice showed significantly lower expression of Nlrp3 in their BAT. Overall, our data suggest that the role of mitophagy is different from general autophagy in regulating adipose tissue and whole-body energy metabolism. Our results uncovered a new mitochondria-NLRP3 pathway that induces BAT dysfunction. The ability of the nlrp3 knockouts to rescue BAT dysfunction suggests the transcriptional function of NLRP3 as an unexpected, but a quite specific therapeutic target for obesity-related metabolic diseases.Abbreviations: ACTB: actin, beta; BAPs: brown adipocyte precursors; BAT: brown adipose tissue; BMDMs: bone marrow-derived macrophages; CASP1: caspase 1; CEBPA: CCAAT/enhancer binding protein (C/EBP), alpha; ChIP: chromatin immunoprecipitation; EE: energy expenditure; HFD: high-fat diet; IL1B: interleukin 1 beta; ITT: insulin tolerance test; KO: knockout; LPS: lipopolysaccharide; NLRP3: NLR family, pyrin domain containing 3; PINK1: PTEN induced putative kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; RD: regular diet; ROS: reactive oxygen species; RT: room temperature; UCP1: uncoupling protein 1 (mitochondrial, proton carrier); WT: wild-type.

Here, we found that heterozygous null of peroxisomal Nudt7 (Nudt7 +/- ) induced the typical NAFLD features, i.e. increased levels of hepatic triglyceride (TG) and fatty acid (FA), infiltration of inflammatory cells, impaired glucose tolerance and insulin sensitivity, and stimulation of lipolysis from adipose tissue. Particularly, in Nudt7 +/- hepatocytes, de novo lipogenesis (DNL) was significantly increased. Ingenuity pathway analysis (IPA) and KEGG pathway analysis of RNA sequencing data suggested the activation of PPAR signaling in the liver of Nudt7 +/- mice. Moreover, accumulation of palmitic acid in Nudt7 +/- hepatocyte increased the level of H3K4me3 on the promoters of PPARγ resulting in the activation of PPARγ and induced the DNL in the hepatocytes of Nudt7 +/- mice. Moreover, we found that liraglutide significantly reduced typical NAFLD features induced by NUDT7 deficiency. Our data suggest that dysregulation of peroxisomal NUDT7 is responsible for upregulation of hepatic DNL by accumulation of palmitic acid and PPARγ activation.