In vivo adenine base editing rescues adrenoleukodystrophy in a humanized mouse model.

X-linked adrenoleukodystrophy (ALD), an inherited neurometabolic disorder caused by mutations in ABCD1, which encodes the peroxisomal ABC transporter, mainly affects the brain, spinal cord, adrenal glands, and testes. In ALD patients, very-long-chain fatty acids (VLCFAs) fail to enter the peroxisome and undergo subsequent ß-oxidation, resulting in their accumulation in the body. It has not been tested whether in vivo base editing or prime editing can be harnessed to ameliorate ALD. We developed a humanized mouse model of ALD by inserting a human cDNA containing the pathogenic variant into the mouse Abcd1 locus. The humanized ALD model showed increased levels of VLCFAs. To correct the mutation, we tested both base editing and prime editing and found that base editing using ABE8e(V106W) could correct the mutation in patient-derived fibroblasts at an efficiency of 7.4%. Adeno-associated virus (AAV)-mediated systemic delivery of NG-ABE8e(V106W) enabled robust correction of the pathogenic variant in the mouse brain (correction efficiency: ∼5.5%), spinal cord (∼5.1%), and adrenal gland (∼2%), leading to a significant reduction in the plasma levels of C26:0/C22:0. This established humanized mouse model and the successful correction of the pathogenic variant using a base editor serve as a significant step toward treating human ALD disease.

Lipid signatures reflect the function of the murine primary placentation†.

The placenta regulates maternal-fetal communication, and its defect leads to significant pregnancy complications. The maternal and embryonic circulations are primitively connected in early placentation, but the function of the placenta during this developmentally essential period is relatively unknown. We thus performed a comparative proteomic analysis of the placenta before and after primary placentation and found that the metabolism and transport of lipids were characteristically activated in this period. The placental fatty acid (FA) carriers in specific placental compartments were upregulated according to gestational age, and metabolomic analysis also showed that the placental transport of FAs increased in a time-dependent manner. Further analysis of two mutant mice models with embryonic lethality revealed that lipid-related signatures could reflect the functional state of the placenta. Our findings highlight the importance of the nutrient transport function of the primary placenta in the early gestational period and the role of lipids in embryonic development. SUMMARY SENTENCE: The placenta is activated characteristically in terms of lipid transport during primary placentation, and the lipid-related signatures closely reflect the functional state of the placenta.

Absence of progesterone receptor membrane component 1 reduces migration and metastasis of breast cancer.

BACKGROUND: Progesterone receptor membrane component 1 (Pgrmc1) is a non-classical progesterone receptor associated with the development of the mammary gland and xenograft-induced breast cancer. Importantly, Pgrmc1 is associated with the expression of estrogen receptor alpha and can be used for predicting the prognosis of breast cancer. Whether the genetic deletion of Pgrmc1 affects the progression of breast cancer is still unclear. METHODS: We used MMTV-PyMT transgenic mice that spontaneously develop breast tumors. In backcrossed FVB Pgrmc1 knockout (KO) mice, we monitored the development of the primary tumor and lung metastasis. In MCF-7 and MDA-MB-231 tumor cell lines, the migratory activity was evaluated after Pgrmc1 knockdown. RESULTS: There was no significant difference in the development of breast cancer in terms of tumor size at 13 weeks of age between WT and Pgrmc1 KO mice. However, Pgrmc1 KO mice had a significantly longer survival duration compared with WT mice. Furthermore, Pgrmc1 KO mice exhibited a significantly lower degree of lung metastasis. Compared with those of WT mice, the tumors of Pgrmc1 KO mice had a low expression of focal adhesion kinase and epithelial-mesenchymal transition markers. PGRMC1 knockdown resulted in a significantly reduced migration rate in breast cancer cell lines. CONCLUSIONS: Pgrmc1 KO mice with breast cancer had a prolonged survival, which was accompanied by a low degree of lung metastasis. PGRMC1 showed a significant role in the migration of breast cancer cells, and may serve as a potential therapeutic target in breast cancer. Video Abstract.

Progesterone receptor membrane component 1 is required for mammary gland development†.

The physiological functions of progesterone (P4) in female reproductive organs including the mammary glands are mediated via the progesterone receptor (PR), but not all P4 functions can be explained by PR-mediated signaling. Progesterone receptor membrane component 1 (PGRMC1), a potential mediator of P4 actions, plays an important role in the ovary and uterus in maintaining female fertility and pregnancy, but its function in mammary glands has not been elucidated. This study investigated the role of PGRMC1 in mouse mammary gland development. Unlike in the uterus, exogenous estrogen (E2) and/or P4 did not alter PGRMC1 expression in the mammary gland, and Pgrmc1-knockout (KO) mice displayed reduced ductal elongation and side branching in response to hormone treatment. During pregnancy, PGRMC1 was expressed within both the luminal and basal epithelium and gradually increased with gestation and decreased rapidly after parturition. Moreover, although lactogenic capacity was normal after parturition, Pgrmc1 KO resulted in defective mammary gland development from puberty until midpregnancy, while the expression of PR and its target genes was not significantly different between wild-type and Pgrmc1-KO mammary gland. These data suggest that PGRMC1 is essential for mammary gland development during puberty and pregnancy in a PR-independent manner.

PIBF1 regulates trophoblast syncytialization and promotes cardiovascular development.

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.

Progesterone receptor membrane component 1 reduces cardiac steatosis and lipotoxicity via activation of fatty acid oxidation and mitochondrial respiration.

Obesity is implicated in cardiovascular disease and heart failure. When fatty acids are transported to and not adequately oxidized in cardiac cells, they accumulate, causing lipotoxicity in the heart. Since hepatic progesterone receptor membrane component 1 (Pgrmc1) suppressed de novo lipogenesis in a previous study, it was questioned whether cardiac Pgrmc1 protects against lipotoxicity. Hence, we focused on the role of cardiac Pgrmc1 in basal (Resting), glucose-dominant (Refed) and lipid-dominant high-fat diet (HFD) conditions. Pgrmc1 KO mice showed high FFA levels and low glucose levels compared to wild-type (WT) mice. Pgrmc1 KO mice presented low number of mitochondrial DNA copies in heart, and it was concomitantly observed with low expression of TCA cycle genes and oxidative phosphorylation genes. Pgrmc1 absence in heart presented low fatty acid oxidation activity in all conditions, but the production of acetyl-CoA and ATP was in pronounced suppression only in HFD condition. Furthermore, HFD Pgrmc1 KO mice resulted in high cardiac fatty acyl-CoA levels and TG level. Accordingly, HFD Pgrmc1 KO mice were prone to cardiac lipotoxicity, featuring high levels in markers of inflammation, endoplasmic reticulum stress, oxidative stress, fibrosis, and heart failure. In vitro study, it was also confirmed that Pgrmc1 enhances rates of mitochondrial respiration and fatty acid oxidation. This study is clinically important because mitochondrial defects in Pgrmc1 KO mice hearts represent the late phase of cardiac failure.

Loss of PGRMC1 Delays the Progression of Hepatocellular Carcinoma via Suppression of Pro-Inflammatory Immune Responses.

Pgrmc1 is a non-canonical progesterone receptor related to the lethality of various types of cancer. PGRMC1 has been reported to exist in co-precipitated protein complexes with epidermal growth factor receptor (EGFR), which is considered a useful therapeutic target in hepatocellular carcinoma (HCC). Here, we investigated whether Pgrmc1 is involved in HCC progression. In clinical datasets, PGRMC1 transcription level was positively correlated with EGFR levels; importantly, PGRMC1 level was inversely correlated with the survival duration of HCC patients. In a diethylnitrosamine (DEN)-induced murine model of HCC, the global ablation of Pgrmc1 suppressed the development of HCC and prolonged the survival of HCC-bearing mice. We further found that increases in hepatocyte death and suppression of compensatory proliferation in the livers of DEN-injured Pgrmc1-null mice were concomitant with decreases in nuclear factor κB (NF-κB)-dependent production of interleukin-6 (IL-6). Indeed, silencing of Pgrmc1 in murine macrophages led to reductions in NF-κB activity and IL-6 production. We found that the anti-proinflammatory effect of Pgrmc1 loss was mediated by reductions in EGFR level and its effect was not observed after exposure of the EGFR inhibitor erlotinib. This study reveals a novel cooperative role of Pgrmc1 in supporting the EGFR-mediated development of hepatocellular carcinoma, implying that pharmacological suppression of Pgrmc1 may be a useful strategy in HCC treatment.

Progesterone increases blood glucose via hepatic progesterone receptor membrane component 1 under limited or impaired action of insulin.

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.

Knockout rat models mimicking human atherosclerosis created by Cpf1-mediated gene targeting.

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.

Loss of progesterone receptor membrane component 1 promotes hepatic steatosis via the induced de novo lipogenesis.

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 ß-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.