Receptor Deficiency Research Articles

Deficiency of Complement C3a and C5a receptors Does Not Prevent Angiotensin II-Induced Hypertension and Hypertensive End-Organ Damage.

Complement may drive the pathology of hypertension through effects on innate and adaptive immune responses. Recently an injurious role for the anaphylatoxin receptors C3aR (complement component 3a receptor) and C5aR1 (complement component 5a receptor) in the development of hypertension was shown through downregulation of Foxp3+ (forkhead box protein 3) regulatory T cells. Here, we deepen our understanding of the therapeutic potential of targeting both receptors in hypertension. Data from the European Renal cDNA Bank, single cell sequencing and immunohistochemistry were examined in hypertensive patients. The effect of C3aR or C3aR/C5aR1 double deficiency was assessed in two models of Ang II (angiotensin II)-induced hypertension in knockout mice. We found increased expression of C3aR, C5aR1 and Foxp3 cells in kidney biopsies of patients with hypertensive nephropathy. Expression of both receptors was mainly found in myeloid cells. No differences in blood pressure, renal injury (albuminuria, glomerular filtration rate, glomerular and tubulointerstitial injury, inflammation) or cardiac injury (cardiac fibrosis, heart weight, gene expression) between control and mutant mice was discerned in C3aR-/- as well as C3aR/C5aR1-/- double knockout mice. The number of renal Tregs was not decreased in Ang II as well as in DOCA salt induced hypertension. Hypertensive nephropathy in mice and men is characterized by an increase of renal regulatory T cells and enhanced expression of anaphylatoxin receptors. Our investigations do not corroborate a role for C3aR/C5aR1 axis in Ang II-induced hypertension hence challenging the concept of anaphylatoxin receptor targeting in the treatment of hypertensive disease.

FRI091 Treatment Of Secondary Hyperlipidemia Due To Nephrotic Syndrome

Abstract Disclosure: J. Girard: None. H. Quadri: None. B. Jiang: None. B.K. Force: None. L. Abushamat: None. R.S. Aguirre: None. Introduction: Secondary Hyperlipidemia associated with nephrotic syndrome contributes to significant cardiovascular morbidity. The elevated atherogenic lipoprotein levels are caused by upregulation of HMG-CoA reductase and downregulation of lipoprotein lipase. More recently, studies in mice have linked PCSK9 and Inducible Degrader of the LDL Receptor (IDOL) as primary contributors to hypercholesterolemia in nephrotic syndrome due to the decrease in LDL receptor recycling (1). Treating nephrotic syndrome is the first-line treatment for the associated secondary hyperlipidemia. Since exposure time to atherogenic lipoproteins matters in the development of cardiovascular disease, statins, with or without ezetimibe, are utilized. PCSK9 inhibitors are initiated if LDL remains elevated despite these measures. This case report highlights a severe case of hypercholesterolemia associated with nephrotic syndrome and treatment response. Clinical Case: A 55-year-old male with no significant past medical history presented to the emergency department with shortness of breath and lower extremity edema. He denied a family and personal history of premature cardiovascular disease. Initial evaluation revealed a serum total cholesterol on 10x dilution of 833.9 (</=200mg/dL), calculated LDL 718mg/dL (<100mg/dL), triglycerides 381mg/dL (<150mg/dL), HDL 39.3mg/dL (40-60mg/dL), Apo B >400mg/dL (<90mg/dL), and Lp(a) 17.5mg/dL (<75mg/dL). His serum albumin was <1.5g/dL (4.2-4.5g/dL), creatinine 2mg/dL (0.7-1.3mg/dL), and 24-hour calculated urinary protein level 10,294mg/24-hour (30-150mg/24-hour). A kidney biopsy revealed a mixed Type III and Type V Lupus Nephritis. The patient started lupus treatment along with atorvastatin 80mg qHS, fenofibrate 45mg daily, and ezetimibe 10mg daily. His LDL decreased to 418mg/dL (<100mg/dL) after 15 days. The patient continued to have undetectable albumin although kidney function improved after 2 months. We planned to initiate PCSK9 inhibitor treatment for further LDL reduction pending treatment of lupus, but patient died from septic shock prior to initiation. Conclusion: This case illustrates that extremely elevated LDL levels from nephrotic syndrome resulted in a nearly 60% reduction of LDL with statin and ezetimibe treatment. Statins, ezetimibe and PCSK9 inhibitor therapy should be considered stepwise when treating secondary hyperlipidemia from nephrotic syndrome. 1. LIU S, VAZIRI ND. ROLE OF PCSK9 AND IDOL IN THE PATHOGENESIS OF ACQUIRED LDL RECEPTOR DEFICIENCY AND HYPERCHOLESTEROLEMIA IN NEPHROTIC SYNDROME. NEPHROL DIAL TRANSPLANT. 2014 MAR;29(3):538-43. DOI: 10.1093/NDT/GFT439. EPUB 2013 OCT 28. PMID: 24166456 Presentation: Friday, June 16, 2023

THU481 Glucocorticoid Regeneration By Tumor Cells Promotes Growth By Enhancing Regulatory T Cell Immunosuppression

Abstract Disclosure: M.D. Taves: None. S. Otsuka: None. M.A. Taylor: None. K.M. Donahue: None. J.D. Ashwell: None. Glucocorticoids are steroid hormones with potent immunosuppressive properties. Their primary source is the adrenals, where they are generated via de novo synthesis from cholesterol. In addition, many tissues have a recycling pathway in which glucocorticoids are regenerated from inactive metabolites by the enzyme 11β-HSD1 (encoded by Hsd11b1). We found that multiple tumor types express Hsd11b1 and produce active glucocorticoids. Genetic ablation of Hsd11b1 in such cells had no effect on in vitro growth but reduced in vivo tumor progression, which corresponded to increased frequencies of tumor-infiltrating cytotoxic T cells expression activation markers and producing effector cytokines. Tumor-derived glucocorticoids upregulated tumor-infiltrating regulatory T cell (Treg) expression of miRNA-342 and downregulated the mTORC2 component Rictor, enhancing Treg activity. Indeed, cytotoxic T cell activation was restored and tumor growth reduced in mice with Treg-specific glucocorticoid receptor deficiency. Importantly, pharmacological inhibition of 11β-HSD1 reduced tumor growth to the same degree as gene knockout, and rendered immunotherapy-resistant tumors susceptible to immune checkpoint blockade. Given that HSD11B1 is upregulated in many human tumors and that inhibition of 11β-HSD1 is well-tolerated in clinical studies, these data suggest that targeting 11β-HSD1 may be a beneficial adjunct in cancer therapy. Presentation: Thursday, June 15, 2023

High maternal adiposity during pregnancy programs an imbalance in the lipidome and predisposes to diet-induced hepatosteatosis in the offspring.

Exposure to high maternal adiposity in utero is a significant risk factor for the later-life development of metabolic syndrome (MetS), including non-alcoholic fatty liver disease (NAFLD). We have previously shown that high pre-pregnancy adiposity programs adipose tissue dysfunction in the offspring, leading to spillover of fatty acids into the circulation, a key pathogenic event in obesity-associated MetS. Herein, we hypothesized that programming of adipose tissue dysfunction in offspring born to overweight dams increases the risk for developing NAFLD. Females heterozygous for leptin receptor deficiency (Hetdb) were used as a model of high pre-pregnancy adiposity. Female wild-type (Wt) offspring born to Hetdb pregnancies gained significantly more body fat following high-fat/fructose diet (HFFD) compared with Wt offspring born to Wt dams. HFFD increased circulating free fatty acids (FFA) in male offspring of control dams, while FFA levels were similar in HFFD-fed offspring from Wt dams and CD or HFFD-fed Wt offspring from Hetdb dams. Despite female-specific protection from diet-induced FFA spillover, both male and female offspring from Hetdb dams were more susceptible to diet-induced hepatosteatosis. Lipidomic analysis revealed that CD-offspring of overweight dams had decreased hepatic polyunsaturated FA (PUFA) levels compared with control offspring. Changes to saturated FA (SFA) and the de novo lipogenic (DNL) index were diet driven; however, there was a significant effect of the intrauterine environment on FA elongation and Δ9 desaturase activity. High maternal adiposity during pregnancy programs a susceptibility to diet-induced hepatosteatosis.

Induced Pluripotent Stem Cell-Derived Chimeric Antigen Receptor T Cells: The Intersection of Stem Cells and Immunotherapy.

Chimeric antigen receptor (CAR) T cell therapy is a promising cell-based immunotherapy applicable to various cancers. High cost of production, immune rejection, heterogeneity of cell product, limited cell source, limited expandability, and relatively long production time have created the need to achieve a universal allogeneic CAR-T cell product for "off-the-shelf" application. Since the innovation of induced pluripotent stem cells (iPSCs) by Yamanaka et al., extensive efforts have been made to prepare an unlimited cell source for regenerative medicine, that is, immunotherapy. In the autologous grafting approach, iPSCs prepare the desired cell source for generating autologous CAR-T cells through more accessible and available sources. In addition, generating iPSC-derived CAR-T cells is a promising approach to achieving a suitable source for producing an allogeneic CAR-T cell product. In brief, the first step is reprogramming somatic cells (accessible from peripheral blood, skin, etc.) to iPSCs. In the next step, CAR expression and T cell lineage differentiation should be applied in different arrangements. In addition, in an allogeneic manner, human leukocyte antigen/T cell receptor (TCR) deficiency should be applied in iPSC colonies. The allogeneic iPSC-derived CAR-T cell experiments showed that simultaneous performance of HLA/TCR deficiency, CAR expression, and T cell lineage differentiation could bring the production to the highest efficacy in generating allogeneic iPSC-derived CAR-T cells.

Brown adipocyte mineralocorticoid receptor deficiency impairs metabolic regulation in diet-induced obese mice

Activation of brown adipose tissue (BAT) contributes to energy dissipation and metabolic health. Although mineralocorticoid receptor (MR) antagonists have been demonstrated to improve metabolism under obesity, the underlying mechanisms remain incompletely understood. We aimed to evaluate the role of BAT MR in metabolic regulation. After 8 weeks of high-fat diet (HFD) feeding, BAT MR KO (BMRKO) mice manifested significantly increased bodyweight, fat mass, serum fasting glucose, and impaired glucose homeostasis compared with littermate control (LC) mice, although insulin resistance and fasting serum insulin were not significantly changed. Metabolic cage experiments showed no change in O2 consumption, CO2 production, or energy expenditure in obese BMRKO mice. RNA sequencing analysis revealed downregulation of genes related to fatty acid metabolism in BAT of BMRKO-HFD mice compared with LC-HFD mice. Moreover, H&E and immunohistochemical staining demonstrated that BMRKO exacerbated HFD-induced macrophage infiltration and proinflammatory genes in epididymal white adipose tissue (eWAT). BMRKO-HFD mice also manifested significantly increased liver weights and hepatic lipid accumulation, an increasing trend of genes related to lipogenesis and lipid uptake, and significantly decreased genes related to lipolytic and fatty acid oxidation in the liver. Finally, the level of insulin-induced AKT phosphorylation was substantially blunted in eWAT but not liver or skeletal muscle of BMRKO-HFD mice compared with LC-HFD mice. These data suggest that BAT MR is required to maintain metabolic homeostasis, likely through its regulation of fatty acid metabolism in BAT and impacts on eWAT and liver.

Leptin receptor gene deficiency minimally affects osseointegration in rats

Metabolic syndrome represents a cluster of conditions such as obesity, hyperglycaemia, dyslipidaemia, and hypertension that can lead to type 2 diabetes mellitus and/or cardiovascular disease. Here, we investigated the influence of obesity and hyperglycaemia on osseointegration using a novel, leptin receptor-deficient animal model, the Lund MetS rat. Machined titanium implants were installed in the tibias of animals with normal leptin receptor (LepR+/+) and those harbouring congenic leptin receptor deficiency (LepR−/−) and were left to heal for 28 days. Extensive evaluation of osseointegration was performed using removal torque measurements, X-ray micro-computed tomography, quantitative backscattered electron imaging, Raman spectroscopy, gene expression analysis, qualitative histology, and histomorphometry. Here, we found comparable osseointegration potential at 28 days following implant placement in LepR−/− and LepR+/+ rats. However, the low bone volume within the implant threads, higher bone-to-implant contact, and comparable biomechanical stability of the implants point towards changed bone formation and/or remodelling in LepR−/− rats. These findings are corroborated by differences in the carbonate-to-phosphate ratio of native bone measured using Raman spectroscopy. Observations of hypermineralised cartilage islands and increased mineralisation heterogeneity in native bone confirm the delayed skeletal development of LepR−/− rats. Gene expression analyses reveal comparable patterns between LepR−/− and LepR+/+ animals, suggesting that peri-implant bone has reached equilibrium in healing and/or remodelling between the animal groups.

Tumors produce glucocorticoids by metabolite recycling, not synthesis, and activate Tregs to promote growth.

Glucocorticoids are steroid hormones with potent immunosuppressive properties. Their primary source is the adrenals, where they are generated via de novo synthesis from cholesterol. In addition, many tissues have a recycling pathway in which glucocorticoids are regenerated from inactive metabolites by the enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1, encoded by Hsd11b1). Here, we find that multiple tumor types express Hsd11b1 and produce active glucocorticoids. Genetic ablation of Hsd11b1 in such cells had no effect on in vitro growth, but reduced in vivo tumor progression, which corresponded with increased frequencies of CD8+ tumor-infiltrating lymphocytes (TILs) expressing activation markers and producing effector cytokines. Tumor-derived glucocorticoids were found to promote signatures of Treg activation and suppress signatures of conventional T cell activation in tumor-infiltrating Tregs. Indeed, CD8+ T cell activation was restored and tumor growth reduced in mice with Treg-specific glucocorticoid receptor deficiency. Importantly, pharmacologic inhibition of 11β-HSD1 reduced tumor growth to the same degree as gene knockout and rendered immunotherapy-resistant tumors susceptible to PD-1 blockade. Given that HSD11B1 expression is upregulated in many human tumors and that inhibition of 11β-HSD1 is well tolerated in clinical studies, these data suggest that targeting 11β-HSD1 may be a beneficial adjunct in cancer therapy.

A National Multicenter Study of Leptin (LEP) and Leptin Receptor (LEPR) deficiency and systematic review

A National Multicenter Study of Leptin (LEP) and Leptin Receptor (LEPR) deficiency and systematic review

Congenital leptin receptor deficiency: A novel leptin receptor gene mutation in an Indian family producing severe early-onset monogenic obesity

Congenital leptin receptor (LEPR) deficiency is a rare autosomal recessive condition producing early-onset severe monogenic obesity with around 90 cases reported worldwide to date. It is associated with early-onset obesity, hyperphagia, and various hormone deficiencies. We describe siblings born to consanguineous parents with progressive early-onset obesity associated with hyperphagia. Genetic analysis revealed a novel homozygous mutation in LEPR (c.1752G>A) gene on chromosome 1p31. Both parents were heterozygous carriers for the same mutation. This is only the second reported case from India where siblings have been affected with LEPR gene mutation. This will provide further insight into the physiologic role of leptin and its receptor LEPR in monogenic obesity.

High morbidity and mortality in children with untreated congenital deficiency of leptin or its receptor

The long-term clinical outcomes of severe obesity due to leptin signaling deficiency are unknown. We carry out a retrospective cross-sectional investigation of a large cohort of children with leptin (LEP), LEP receptor (LEPR), or melanocortin 4 receptor (MC4R) deficiency (n= 145) to evaluate the progression of the disease. The affected individuals undergo physical, clinical, and metabolic evaluations. We report a very high mortality in children with LEP (26%) or LEPR deficiency (9%), mainly due to severe pulmonary and gastrointestinal infections. In addition, 40% of surviving children with LEP or LEPR deficiency experience life-threatening episodes of lung or gastrointestinal infections. Although precision drugs are currently available for LEP and LEPR deficiencies, as yet, they are not accessible in Pakistan. An appreciation of the severe impact of LEP or LEPR deficiency on morbidity and early mortality, educational attainment, and the attendant stigmatization should spur efforts to deliver the available life-saving drugs to these children as a matter of urgency.

Effect of Growth Hormone Receptor Deficiency on Androgen-Associated Gene Expression of Hepatic Drug Metabolizing Enzymes and Drug Transporters in Pigs.

Growth hormone receptor (GHR)-deficient pigs were generated using the CRISPR/Cas9 system to investigate the involvement of GHR-mediated growth hormone (GH) signaling in androgen-associated gene expression of hepatic drug metabolizing enzymes (DMEs) and drug transporters. We initially confirmed that no wild-type GHR mRNA was present in GHR-/- (GHR-KO) pigs; in addition, as previously reported, those pigs exhibited decreases in body weight and serum insulin-like growth factor-1 concentration and an increase in serum GH concentration compared with the levels in GHR-/+ and GHR+/+ pigs with a wild-type GHR mRNA. The real-time RT-PCR results on the mRNA levels of hepatic DMEs and drug transporters in the GHR-KO pigs and the pigs with a wild-type GHR mRNA revealed that, among the examined hepatic DMEs, the mRNA levels of CYP1A2, CYP2A19, sulfotransferase (SULT) 1A1, and SULT2A1 were higher in GHR-KO pigs than in the pigs with a wild-type GHR mRNA, whereas the opposite trend was observed for the mRNA level of uridine 5'-diphospho-glucuronosyltransferase 1A6. No such significant differences in the mRNA levels of three hepatic drug transporters including multidrug resistance protein 1 were observed. In addition, the mRNA level of hepatic cut-like homeobox 2 (CUX2), which is expressed in an androgen-dependent manner and associated with the hepatic mRNA expression of several DMEs, was significantly decreased in GHR-KO pigs. The present findings strongly suggest that not only serum androgen but also GHR-mediated GH signaling contributes to the mRNA expression of several DMEs and CUX2, but not transporters, in the pig liver.

Correction to Dual deficiency of angiotensin-converting enzyme-2 and Mas receptor enhances angiotensin II-induced hypertension and hypertensive nephropathy.

Correction to Dual deficiency of angiotensin-converting enzyme-2 and Mas receptor enhances angiotensin II-induced hypertension and hypertensive nephropathy.

Regulation and function of adiponectin in the intestinal epithelial cells in response to Trichinella spiralis infection

Besides metabolic homeostasis regulation, adipokines are recently emerged as important players in regulating immunity and inflammation. Helminth infection has known to modulate circulating adipokine secretion; however, the regulation and function of adipokines in response to helminth infection is still unclear. Here, we investigated the regulation and function of adiponectin during T. spiralis infection. While there was no change in circulating level of adiponectin, we found an increased adiponectin, but not leptin expression in the small intestine. Interestingly, the intestinal adiponectin expression was strongly associated with the expression of epithelial cell-derived cytokines IL-25, IL-33, and TSLP following infection. Indeed, mice deficiency of IL-25 receptor exhibited no intestinal adiponectin induction upon helminth infection. Interestingly, IL-25-induced adiponectin modulated intestinal epithelial cell responses by enhancing occludin and CCL17 expression. Using LPS-induced intestinal epithelial barrier dysfunctions in a Caco-2 cell monolayer model, adiponectin pretreatment enhanced a Transepithelial electrical resistance (TEER) and occludin expression. More importantly, adiponectin pretreatment of Caco2 cells prevented T. spiralis larval invasion in vitro and its administration during infection enhanced intestinal IL-13 secretion and worm expulsion in vivo. Altogether, our data suggest that intestinal adiponectin expression induced by helminth infection through the regulation of IL-25 promotes worm clearance and intestinal barrier function.

Photodynamic therapy potential of cobalt phthalocyanine in triple-negative breast cancer

Triple-negative breast cancer (TNBC) has the worst prognosis among breast cancers. The deficiency of hormone receptors (ER-/PR-/HER-2-) limits treatment options. Photodynamic therapy (PDT) is a safe treatment method for target-specific applications and has no toxic side effects. In this study, the efficacy of PDT on TNBC cells after activation of phthalocyanine derivative CoPc-COOH with RED light was investigated. The cytotoxicity of CoPc-COOH in MDA-MB-231 cells was evaluated at 24, 48, and 72 h. To detect phototoxic activity, cells were exposed simultaneously to a dose range of CoPc-COOH at 48th hours and 20, 30, 40, and 50 J/cm2 RED light in a laser source with an output fluorescence of 12 mW/cm2. The apoptotic effect of single CoPc-COOH, RED light, and their combinations were examined by using the Annexin V method and the ROS generation potential using the carboxy-H2-DCFH-DA test in flow cytometry. DCF fluorescence intensity of control and dose groups were taken under the fluorescence microscope. The IC50 values of CoPc-COOH in MDA-MB-231 cells at the 24th, 48th, and 72nd hours were calculated as 131.04 µM, 66.75 µM, and 59.74 µM, respectively. In the phototoxicity test, 50 J/cm2 application increased the IC50 dose of CoPc-COOH to 73.73 µM; 20, 30, 40 J/cm2 application reduced the doses to 2.31 µM, 0.20 µM, and 28.14 µM, respectively. Compared to the untreated group, it was determined that ROS formation and apoptotic stimulation were triggered significantly in treatment groups. A combination of CoPc-COOH and 40 J/cm2 showed the highest synergistic effect.

Selective neuroimmune modulation by type I interferon drives neuropathology and neurologic dysfunction following traumatic brain injury.

Accumulating evidence suggests that type I interferon (IFN-I) signaling is a key contributor to immune cell-mediated neuropathology in neurodegenerative diseases. Recently, we demonstrated a robust upregulation of type I interferon-stimulated genes in microglia and astrocytes following experimental traumatic brain injury (TBI). The specific molecular and cellular mechanisms by which IFN-I signaling impacts the neuroimmune response and neuropathology following TBI remains unknown. Using the lateral fluid percussion injury model (FPI) in adult male mice, we demonstrated that IFN α/β receptor (IFNAR) deficiency resulted in selective and sustained blockade of type I interferon-stimulated genes following TBI as well as decreased microgliosis and monocyte infiltration. Molecular alteration of reactive microglia also occurred with diminished expression of genes needed for MHC class I antigen processing and presentation following TBI. This was associated with decreased accumulation of cytotoxic T cells in the brain. The IFNAR-dependent modulation of the neuroimmune response was accompanied by protection from secondary neuronal death, white matter disruption, and neurobehavioral dysfunction. These data support further efforts to leverage the IFN-I pathway for novel, targeted therapy of TBI.

Vitamin D Receptor Deficiency Upregulates Pulmonary Artery Kv7 Channel Activity.

Recent evidence suggests that vitamin D is involved in the development of pulmonary arterial hypertension (PAH). The aim of this study was to analyze the electrophysiological and contractile properties of pulmonary arteries (PAs) in vitamin D receptor knockout mice (Vdr-/-). PAs were dissected and mounted in a wire myograph. Potassium membrane currents were recorded in freshly isolated PA smooth muscle cells (PASMCs) using the conventional whole-cell configuration of the patch-clamp technique. Potential vitamin D response elements (VDREs) in Kv7 channels coding genes were studied, and their protein expression was analyzed. Vdr-/- mice did not show a pulmonary hypertensive phenotype, as neither right ventricular hypertrophy nor endothelial dysfunction was apparent. However, resistance PA from these mice exhibited increased response to retigabine, a Kv7 activator, compared to controls and heterozygous mice. Furthermore, the current sensitive to XE991, a Kv7 inhibitor, was also higher in PASMCs from knockout mice. A possible VDRE was found in the gene coding for KCNE4, the regulatory subunit of Kv7.4. Accordingly, Vdr-/- mice showed an increased expression of KCNE4 in the lungs, with no changes in Kv7.1 and Kv7.4. These results indicate that the absence of Vdr in mice, as occurred with vitamin D deficient rats, is not sufficient to induce PAH. However, the contribution of Kv7 channel currents to the regulation of PA tone is increased in Vdr-/- mice, resembling animals and humans suffering from PAH.

A Case-Control Study of the Relationship Between Genetic Polymorphism and Cretinism in Xinjiang.

Cretinism is a subtype of congenital hypothyroidism, an endocrine disorder resulting from inadequate thyroid hormone production or receptor deficiency. Genetic abnormalities play a major role in the development of thyroid dysfunction. We recruited 183 participants with cretinism and 119 healthy participants from the Xinjiang Uyghur Autonomous Region and randomly selected 29 tag single nucleotide polymorphisms (tSNPs) in TSHB, PAX8, TPO, NKX2-5, and TSHR in all participants. We compared genotype and allele frequencies between cases and controls utilizing the chi-squared test, logistic regression analysis, and haplotype analysis. Using the chi-squared test, a single SNP was found to be associated with cretinism (recessive model: rs3754363, OR = 0.46, 95% CI = 0.27-0.80, P = 0.00519; genotype model: P = 0.01677). We stratified neurological, myxedematous, and mixed type and determined that another SNP was associated with a higher risk when comparing myxedematous type to the neurological type (rs2277923). rs3754363 has a statistically significant protective effect on people with cretinism, while rs2277923 may play a greater role in promoting the development of neurocretinism.

Deficiency of olfactory receptor 2 worsens cardiac function and increases infarct size after myocardial infarction

Deficiency of olfactory receptor 2 worsens cardiac function and increases infarct size after myocardial infarction

Placental deficiency of the (pro)renin receptor ((P)RR) reduces placental development and functional capacity.

The (pro)renin receptor ((P)RR; also known as ATP6AP2) is a multifunctional receptor. The (P)RR activates the tissue renin-angiotensin system (RAS) and is also involved in regulating integral intracellular pathways such as V-ATPase and Wnt/β-catenin signalling. Given this, the (P)RR may be associated with essential pathways in placentation, however its role within the context of pregnancy remains poorly characterised. The first trimester/extravillous trophoblast cell line, HTR-8/SVneo, underwent an siRNA knockdown where they were incubated for 24h with a negative control siRNA or siRNA targeting ATP6AP2 mRNA. xCELLigence real-time cell analysis was performed to assess the effect of ATP6AP2 mRNA knockdown on HTR-8/SVneo cell proliferation, migration, and invasion. In subsequent experiments, GFP-encoding lentiviral packaged gene-constructs were used to knockdown (P)RR expression in the trophectoderm of C57/BL6/CBA-F1 mouse blastocysts. Blastocysts were incubated for 6h with vehicle (no-virus), control virus (non-targeting shRNA and GFP), or (P)RR-knockdown virus ((P)RR shRNA and GFP) before transfer into recipient pseudo-pregnant Swiss CD1 female mice. Fetal and placental tissues were collected and assessed at embryonic age (EA) 10 and 18. (P)RR levels were measured in the labyrinth zone of day 18 placentae and stereological Merz grid analysis was performed to determine the volumetric distribution of trophoblasts, fetal capillaries, and the maternal blood space. We showed that a reduction of ATP6AP2 expression in HTR-8/SVneo cells in vitro, impaired trophoblast proliferation, migration, and invasion. In vivo, decreasing placental labyrinth (P)RR expression adversely effected placental physiology, decreasing placental trophoblast number and total surface area available for exchange, while also increasing maternal blood space. Additionally, decreased (P)RR affected placental efficacy evident by the reduced fetal-placental weight ratio. Our study shows that the (P)RR is necessary for appropriate placental development and function.