Abundant Expression Research Articles

The inhibition of FKBP5 protects β-cell survival under inflammation stress via AKT/FOXO1 signaling

The FK506-binding protein 51 (FKBP51, encoded by FKBP5 gene) has emerged as a critical regulator of mammalian endocrine stress responses and as a potential pharmacological target for metabolic disorders, including type 2 diabetes (T2D). However, in β cells, which secrete the only glucose-lowering hormone—insulin, the expression and function of FKBP5 has not been documented. Here, using human pancreatic tissue and primary human islets, we demonstrated the abundant expression of FKBP5 in β cells, which displayed an responsive induction upon acute inflammatory stress mimicked by in vitro treatment with a cocktail of inflammatory cytokines (IL-1β, IFN-γ, and TNF-α). To explore its function, siRNAs targeting FKBP5 and pharmacological inhibitor SAFit2 were applied both in clonal NIT-1 cells and primary human/mice islets. We found that FKBP5 inhibition promoted β-cell survival, improved insulin secretion, and upregulated β-cell functional gene expressions (MAFA and NKX6.1) in acute-inflammation stressed β cells. In primary human and mice islets, which constitutively suffer from inflammation stress during isolation and culture, FKBP5 inhibition also presented decent performance in improving islet function, in accordance with its protective effect against inflammation. Molecular studies found that FKBP5 is an important regulator for FOXO1 phosphorylation at Serine 256, and silencing of FOXO1 abrogated the protective effect of FKBP5 inhibition, suggesting that it is the key downstream effector of FKBP5 in β cells. At last, in situ detection of FKBP5 protein expression on human and mice pancreases revealed a reduction of FKBP5 expression in β cells in human T2D patients, as well as T2D mice model (db/db), which may indicate a FKBP5-inhibition-mediated pro-survival mechanism against the complex stresses in T2D milieus.

Cloning and expression characterization of elongation of very long-chain fatty acids protein 6 (elovl6) with dietary fatty acids, ambient salinity and starvation stress in Scylla paramamosain.

Introduction: Elongation of very long-chain fatty acids protein 6 (ELOVL6) played crucial roles in regulating energy expenditure and fatty acid metabolism. Many studies have performed to investigate the physiological roles and regulatory mechanisms of elovl6 in fish and animals, while few studies were reported in crustaceans. Methods: Here we reported on the molecular cloning, tissue distribution and expression profiles in response to dietary fatty acids, ambient salinity and starvation stress in Scylla paramamosain by using rapid amplification of cDNA ends (RACE) and quantitative real-time PCR. Results: Three elovl6 isoforms (named elovl6a, elovl6b and elovl6c) were isolated from S. paramamosain in the present study. The complete sequence of elovl6a was 1345 bp, the full-length sequence of elovl6b was 1419 bp, and the obtained elovl6c sequence was 1375 bp in full length. The elovl6a, elovl6b and elovl6c encoded 287, 329 and 301 amino acids respectively, and exhibited the typical structural features of ELOVL protein family members. Phylogenetic analysis showed that the ELOVL6a from S. paramamosain clustered most closely to ELOVL6 from Portunus trituberculatus and Eriocheir sinensis, while the ELOVL6b and ELOVL6c from S. paramamosain gathered alone into a single branch. Quantitative real-time PCR exhibited that the relatively abundant expression of elovl6b was observed in intestine and stomach, and the elovl6a and elovl6c were highly expressed in hepatopancreas. In addition, studies found that replacing fish oil with soybean oil could significantly increase the transcriptional levels of three elovl6 in hepatopancreas of S. paramamosain, and the expression of elovl6a and elovl6c in hepatopancreas were more sensitive to dietary fatty acids than the elovl6b. Compared with the normal sea water group (27‰), the expression of sterol-regulatory element binding protein1c (srebp-1), elovl6a, elovl6b and elovl6c were upregulated in the low salinity groups, particularly in 7‰. On the contrary, the starvation stress suppressed the expression of srebp-1, elovl6a, elovl6b and elovl6c. Discussion: These results may contribute to understand the functions of elovl6 in fatty acid synthesis and regulatory mechanisms in crustaceans.

Sweet taste preference is associated with greater hypothalamic response to glucose and longitudinal weight gain

The hypothalamus has an abundant expression of sweet taste receptors that play a role in glucose sensing and energy homeostasis. Evidence suggests that liking “sweets” can be associated with weight gain, but the relationship between sweet taste preference and hypothalamic regulation of appetite is unknown. This study tested the hypothesis that sweet taste preference is associated with increased hypothalamic activation in response to glucose (a purported neural marker for weight gain risk) and greater longitudinal increases in body mass index (BMI). Fifty-four adults aged 18–35 years with a mean (± SD) BMI of 27.99 ± 5.32 kg/m2 completed the study. Height and weight were measured at baseline and 6–12 months later in a subset of 36 participants. Sweet taste preference was assessed via the Monell 2-series, forced-choice tracking procedure. Arterial spin labeling magnetic resonance imaging was performed before and after oral glucose ingestion to determine hypothalamic blood flow response to glucose. Linear models were used to examine relationships between sweet taste preference and the hypothalamic response to glucose and longitudinal changes in BMI, adjusting for age, sex, and baseline BMI. Sweet taste preference was positively associated with glucose-linked hypothalamic blood flow (beta = 0.017, p = 0.043), adjusted for age, sex and BMI. We also observed a positive association between sweet taste preference and longitudinal change in BMI (beta = 0.088, p = 0.015), adjusted for age, sex and baseline BMI. These findings suggest that heightened sweet taste preference is associated with glucose-linked hypothalamic activation and may be linked to increased susceptibility for weight gain.

EndoC-βH5 cells are storable and ready-to-use human pancreatic beta cells with physiological insulin secretion

ObjectivesReadily accessible human pancreatic beta cells that are functionally close to primary adult beta cells are a crucial model to better understand human beta cell physiology and develop new treatments for diabetes. We here report the characterization of EndoC-βH5 cells, the latest in the EndoC-βH cell family. MethodsEndoC-βH5 cells were generated by integrative gene transfer of immortalizing transgenes hTERT and SV40 large T along with Herpes Simplex Virus-1 thymidine kinase into human fetal pancreas. Immortalizing transgenes were removed after amplification using CRE activation and remaining non-excized cells eliminated using ganciclovir. Resulting cells were distributed as ready to use EndoC-βH5 cells. We performed transcriptome, immunological and extensive functional assays. ResultsReady to use EndoC-βH5 cells display highly efficient glucose dependent insulin secretion. A robust 10-fold insulin secretion index was observed and reproduced in four independent laboratories across Europe. EndoC-βH5 cells secrete insulin in a dynamic manner in response to glucose and secretion is further potentiated by GIP and GLP-1 analogs. RNA-seq confirmed abundant expression of beta cell transcription factors and functional markers, including incretin receptors. Cytokines induce a gene expression signature of inflammatory pathways and antigen processing and presentation. Finally, modified HLA-A2 expressing EndoC-βH5 cells elicit specific A2-alloreactive CD8 T cell activation. ConclusionsEndoC-βH5 cells represent a unique storable and ready to use human pancreatic beta cell model with highly robust and reproducible features. Such cells are thus relevant for the study of beta cell function, screening and validation of new drugs, and development of disease models.

LncRNA H19 aggravates primary graft dysfunction after lung transplantation via KLF5-mediated activation of CCL28

The present study aims to elucidate the possible involvement of H19 in primary graft dysfunction (PGD) following lung transplantation (LT) and the underlying mechanism. The transcriptome data were obtained through high-throughput sequencing analysis, and the differential long noncoding RNAs and messenger RNAs were screened for coexpression analysis. The interaction among H19, KLF5 and CCL28 was analyzed. A hypoxia-induced human pulmonary microvascular endothelial cell injury model was established, in which H19 was knocked down to elucidate its effect on the lung function, inflammatory response, and cell apoptosis. An orthotopic left LT model was constructed for in vivo mechanistic validation. High-throughput transcriptome sequencing analysis revealed the involvement of the H19/KLF5/CCL28 signaling axis in PGD. Silencing of H19 reduced inflammatory response and thus improved PGD. CCL28 secreted by human pulmonary microvascular endothelial cells after LT recruited neutrophils and macrophages. Mechanistic investigations indicated that H19 augmented the expression of CCL28 by binding to the transcription factor KLF5. Abundant expression of CCL28 reversed the alleviating effect of H19 silencing on PGD. In conclusion, the results point out that H19 exerts a promoting effect on PGD through increasing KLF5 expression and the subsequent CCL28 expression. Our study provides a novel insight into the mechanism of action of H19.

Pharmacognostic study and peptidomic analysis of the leaves of Nigerian Rauvolfia vomitoria Wennberg (Apocynaceae)

This study was aimed at documenting some pharmacognostic and peptidomic standards on the leaf of Nigerian species of Rauvolfia vomitoria Wennberg (RVM). Using standard methods, the fresh and dried pulverized leaves of R. vomitoria were standardized macroscopically and microscopically, in addition to the physiochemical evaluation and MALDI TOF/TOF-guided peptidomic screening of the aqueous extracts of the leaf. The leaf is simple, elliptical shaped, crenated margin which is acute. The leaf presented a hexagonal shaped epidermal cell on both sides with anomocytic stomata only on the abaxial surface making it hypostomatous while stomata number and index are 15 – 16 – 18 and 24 – 25 – 26, respectively. The transverse section of the leaf through the midrib suggests that the vascular bundles are conjoint, collateral and closed. Moisture content, total ash, acid insoluble ash, water soluble ash, sulphated ash, water soluble and alcohol soluble extractives were as follows; 7.7 ± 1,5, 4.9 ± 0.7, 1.2 ± 0.8, 4.1 ± 0.2, 4.8 ± 0.9, 3.9 ± 0.9, 8.1 ± 1.7w/w%, respectively. Peptidomic analysis revealed the abundant expression of nature-derived knottin-like peptides with a mass range of 3.1 kDa – 3.7 kDa. Knottin peptides have been reported to perform defense roles in host plants; since they are not ubiquitously distributed in planta, their detection in RVM could be useful in the proper identification of the plant and in RVM chemosystematics. Findings from this study has unveiled some important macroscopic, microscopic and physicochemical standards as well as a new peptidomic phytochemical standard helpful in the proper identification in addition to ensuring the efficacy and safety of the leaf of R. vomitoria.

Metformin Disrupts Signaling and Metabolism in Fetal Hepatocytes.

The major metformin uptake transporter OCT1 is expressed in the fetal liver, and fetal hepatic uptake of metformin is observed invivo. Metformin activates AMPK, reduces glucose production, and decreases oxygen consumption in fetal hepatocytes, demonstrating similar effects as in juvenile hepatocytes. Unique to fetal hepatocytes, metformin activates metabolic stress pathways and alters the expression of secreted growth factors and hepatokines. Disruption of signaling and metabolism with increased stress pathways and reduced anabolic pathways by metformin in the fetal liver may underlie reduced growth in fetuses exposed to metformin.

366-OR: Regulation of Metabolite Pools Influences Adipocyte Differentiation and Antioxidant Capacity

Obesity and related metabolic disorders, such as insulin resistance and type 2 diabetes (T2D), affect over 40% of U.S. adults and increase the risk of death from cardiovascular disease. Understanding the mechanisms connecting obesity, T2D, and defective adipocyte function bring us closer to developing therapeutic strategies. We discovered expression of the enzyme aspartoacylase (ASPA) in white adipose tissue (WAT) correlates with adipocyte function and insulin sensitivity in mice and people. In the brain, ASPA contributes to the acetate pool necessary for lipid synthesis, and ASPA deficiency causes progressive myelin degeneration and death at a young age. We also observed abundant ASPA expression in WAT at significantly higher levels than whole brain. Aspa is induced during adipocyte differentiation in vitro along with known adipogenic markers. These observations led us to hypothesize that ASPA and its metabolite byproducts regulate adipocyte differentiation and systemic energy balance. When assessing the in vivo effects of Aspa deficiency, Aspa-/- mice accumulated less body mass than Aspa+/+ when fed normal chow diet for 12 weeks. Morphometric tissue analyses indicated Aspa-/- mice maintain smaller adipocytes, corresponding with lower WAT mass at necropsy. Glucose tracing experiments suggested Aspa knockout cells exhibit greater pyruvate carboxylase (PC) anaplerosis that feeds amino acid pools for glutathione synthesis. Mass spectrometry data also indicated higher PC anaplerosis in the adipose tissues of Aspa knockout mice. Persistent and prolonged oxidative stress hinders adipocyte function and insulin sensitivity, while PC activity supports antioxidant capacity. In line with this, Aspa knockout cells showed increased expression of proteins that sustain antioxidant activities. In summary, our studies establish a new role for ASPA outside the brain that contributes to redox activities in adipocytes. Disclosure J.B.Felix: None. P.Saha: None. A.Cox: None. R.A.Sharp: None. P.M.Masschelin: None. S.M.Hartig: None. Funding American Diabetes Association (1-18-IBS-105 to S.M.H.); National Institutes of Health (F31DK130596, R01DK114356)

1570-P: Myeloid-Specific Inactivation of Basp1 Protects Mice from Diet-Induced NASH through Attenuating NLRP3 Inflammasome Activation

Nonalcoholic steatohepatitis (NASH) is characterized by persistent liver injury, inflammation, and fibrosis. Myeloid cells, including macrophages and dendritic cells, play an integral role in host defense, tissue homeostasis, and disease progression. Despite this, how myeloid cells contribute to NASH pathogenesis remains obscure. We previously identified NASH-associated macrophages (NAMs) as a unique population of monocyte-derived macrophages in NASH liver. We observed that hepatic NAMs exhibited abundant expression of Brain acid-soluble protein 1 (Basp1), which was markedly induced in the liver upon diet-induced NASH in mice. We generated myeloid-specific Basp1 knockout (Mye-Basp1 KO) mice to determine its role in NASH pathogenesis. Compared to control, Mye-Basp1 KO mice displayed significantly improved liver injury and fibrosis following NASH diet feeding, as shown by lower plasma ALT/AST levels and reduced Sirius Red staining on liver sections, respectively. Hepatocytes from Mye-Basp1 KO mice contained smaller lipid droplets without altering the total liver triglyceride content. Mechanistically, bone marrow-derived macrophages (BMDMs) lacking Basp1 exhibited diminished response to pro-inflammatory stimuli. Importantly, Basp1-deficient BMDMs displayed impaired activation of the NLRP3 inflammasome and secretion of interleukin-1 beta. Together, we propose that Basp1 is a novel regulator of inflammatory signaling in myeloid cells that plays a critical role in NASH pathogenesis. Disclosure Z.Meng: None. L.Zhou: None. S.Hong: None. T.Liu: None. X.Qiu: None. Z.Chen: None. S.Li: None. K.Inoki: None. J.Lin: None. Funding National Institute of Diabetes and Digestive and Kidney Diseases (DK102456)

Pre-emptive iron supplementation prevents myocardial iron deficiency and attenuates adverse remodelling after myocardial infarction.

Heart failure (HF) after myocardial infarction (MI) is a major cause of morbidity and mortality. We sought to investigate the functional importance of cardiac iron status after MI and the potential of pre-emptive iron supplementation in preventing cardiac iron deficiency (ID) and attenuating left ventricular (LV) remodelling. MI was induced in C57BL/6J male mice by left anterior descending coronary artery ligation. Cardiac iron status in the non-infarcted LV myocardium was dynamically regulated after MI: non-haem iron and ferritin increased at 4 weeks but decreased at 24 weeks after MI. Cardiac ID at 24 weeks was associated with reduced expression of iron-dependent electron transport chain (ETC) Complex I compared with sham-operated mice. Hepcidin expression in the non-infarcted LV myocardium was elevated at 4 weeks and suppressed at 24 weeks. Hepcidin suppression at 24 weeks was accompanied by more abundant expression of membrane-localized ferroportin, the iron exporter, in the non-infarcted LV myocardium. Notably, similarly dysregulated iron homeostasis was observed in LV myocardium from failing human hearts, which displayed lower iron content, reduced hepcidin expression, and increased membrane-bound ferroportin. Injecting ferric carboxymaltose (15 µg/g body weight) intravenously at 12, 16, and 20 weeks after MI preserved cardiac iron content and attenuated LV remodelling and dysfunction at 24 weeks compared with saline-injected mice. We demonstrate, for the first time, that dynamic changes in cardiac iron status after MI are associated with local hepcidin suppression, leading to cardiac ID long term after MI. Pre-emptive iron supplementation maintained cardiac iron content and attenuated adverse remodelling after MI. Our results identify the spontaneous development of cardiac ID as a novel disease mechanism and therapeutic target in post-infarction LV remodelling and HF.

RNA-Seq and 16S rRNA Reveals That Tian-Dong-Tang-Gan Powder Alleviates Environmental Stress-Induced Decline in Immune and Antioxidant Function and Gut Microbiota Dysbiosis in Litopenaeus vannami.

Ammonia stress and nitrite stress can induce immune depression and oxidative stress in Litopenaeus vannami (L. vannamei). Earlier reports showed that L. vannamei immunity, resistance to ammonia stress, and resistance to nitrite stress improved after Tian-Dong-Tang-Gan Powder (TDTGP) treatment, but the mechanism is not clear. In this study, three thousand L. vannamei were fed different doses of TDTGP for 35 days and then subjected to ammonia and nitrite stress treatments for 72 h. Transcriptome and 16-Seq ribosomal RNA gene sequencing (16S rRNA-seq) were used to analyze hepatopancreas gene expression and changes in gut microbiota abundance in each group. The results showed that after TDTGP treatment, hepatopancreas mRNA expression levels of immunity- and antioxidant-related genes were increased, the abundance of Vibrionaceae in the gut microbiota was decreased, and the abundance of Rhodobacteraceae and Flavobacteriaceae was increased. In addition, after TDTGP treatment, the effects of ammonia and nitrite stress on the mRNA expression of Pu, cat-4, PPAF2, HO, Hsp90b1, etc. were reduced and the disruption of the gut microbiota was alleviated. In short, TDTGP can regulate the immunity and antioxidant of L. vannamei by increasing the expression levels of immunity- and antioxidant-related genes and regulating the abundance of Rhodobacteraceae and Flavobacteriaceae in the gut microbiota.

The effect of dietary docosahexaenoic acid (DHA; 22:6n-3) on photoreceptor abundance, rhodopsin expression and growth in developing gilthead sea bream (Sparus aurata) larvae

This study determined the effect of prey DHA on larval gilthead sea bream (GSB; Sparus aurata) photoreceptor abundance, rhodopsin expression, and growth performance. It was carried out in a twenty-eight 400 l conical tank system that was stocked with 100 viable GSB eggs/l/tank. This allowed the testing of 4 levels of rotifer DHA; 0.99 (Low; L), 1.9 (Intermediate low; I-L), 3.2 (Intermediate high; I-H) and 12.1(High; H) mg DHA/g DW rotifer, which were fed (10 rotifers/ml) to 3-16 DPH larvae. These rotifer diets continued to be offered to 17-34 DPH fish, although these larvae predominantly fed on 4 DHA enriched Artemia nauplii treatments that were offered at a concentration from 0.1 nauplii/ml to 4 nauplii/ml, depending on larval age. This resulted in 4 DHA rotifer-Artemia ranges: 0.99-0.0 (L), 1.9-2.6 (I-L), 3.2-7.2 (I-H), and 12.1-11.77 (H) mg DHA/g DW. The 4 DHA treatments and ranges were tested in replicates of 7 conical tanks per treatment. Increasing rotifer DHA significantly (P<0.0001) improved TL, in an exponential manner, throughout larval rearing. DW in 34 DPH larvae was markedly (P<0.05) enhanced with dietary DHA inclusion in the rotifers and Artemia. There was a significant (P < 0.005) prey DHA dose dependent range effect on the abundance of photoreceptor cells in the retina of 34 DPH larvae. The gene expression of rhodopsin in GSB larvae was significantly (P<0.05) upregulated with dietary DHA dose range and larval age (P<0.0001). This study established a link between dietary DHA level with photoreceptor abundance and rhodopsin expression, which led to improved vision, prey acquisition, and growth in developing GSB larvae.

Withania somnifera inhibits photorefractoriness which triggers neuronal apoptosis in both pre-optic and paraventricular hypothalamic area of Coturnix coturnix japonica: involvement of oxidative stress induced p53 dependent Caspase-3 mediated low immunoreactivity of estrogen receptor alpha.

Light has a very important function in the regulation of the normal physiology including the neuroendocrine system, biological rhythms, cognitive behavior, etc. The variation in photoperiod acts as a stressor due to imbalance in endogenous hormones. Estrogen and its receptors ER alpha and beta play a vital role in the control of stress response in birds. The study investigates the estrogenic effects of a well-known medicinal plant Withania somnifera (WS), mediated by estrogen receptor alpha (ERα) in the hypothalamic pre-optic area (POA) and paraventricular nuclei (PVN). Further the study elucidates its anti-oxidants and anti-apoptotic activities in the brain of Japanese quail. To validate this hypothesis, mature male quails were exposed to long day length for 3months and then transferred to intermediate day length to become photorefractory (PR) while controls were still continued under long daylength. Supplementation of WS root extract in PR quail increases plasma estrogen and lowers corticosterone. Further, in PR quail the variation in light downregulates immunoreactivity of ERα, oxidative stress and antioxidant enzyme activities i.e. superoxide dismutase and catalase in the brain. Neuronal apoptosis was observed in the POA and PVN of PR quail as indicated by the abundant expression of Caspase-3 and p53 which reduces after the administration of WS root extract. The neuronal population also found to decrease in PR although it increased in WS administered quails. Further, the study concluded that change in photoperiod from 3months exposure of 16L: 8D to 13.5L: 10.5D directly activates neuronal apoptosis via expression of Caspase3 and p53 expression in the brain and increases neuronal and gonadal oxidative stress while WS root extract reverses them via enhanced estrogen and its receptor ERα expression in the hypothalamic pre-optic and PVN area of Japanese quail.

Histological demonstration of gonad development in the banana shrimp, Fenneropenaeus merguiensis

The genetic diversity of the banana shrimp Fenneropenaeus merguiensis is at risk because of over-harvesting, which consequently reduces food security. This endangerment is exacerbated because this species is not commonly cultivated by farmers. Overall, these factors necessitate conservation of this shrimp species across its natural habitat. Information on the migration of primordial germ cells (PGCs) to form a gonad is essential for shrimp preservation techniques such as broodstock preparation, sex differentiation, and germ cell transplantation. In this study, histological analysis and in situ hybridization of vasa expression (from embryo to testis development) were used to demonstrate the movement of PGCs. Hematoxylin and Eosin staining and in situ hybridization with the VASA probe revealed that the PGCs migrated retrogradely along the midgut, colonizing the area between the hepatopancreas and heart, a region that becomes the genital ridge in the postlarval stage. External sexual organs appeared at approximately 4 months of age. Through real-time PCR, the expression of the vasa gene was detected early on postlarval day 7, whereas its abundant expression was detected in the ovaries and testes of adult shrimp. This study could help with the identification and monitoring of PGCs or spermatogonia in banana shrimp and facilitate the implementation of other germ cell-relevant techniques in the future.

Integrated Analysis of Single-Cell RNA-Seq and Bulk RNA-Seq Combined with Multiple Machine Learning Identified a Novel Immune Signature in Diabetic Nephropathy.

Increasing evidence suggests that immune modulation contributes to the pathogenesis and progression of diabetic nephropathy (DN). However, the role of immune modulation in DN has not been elucidated. The purpose of this study was to search for potential immune-related therapeutic targets and molecular mechanisms of DN. Gene expression datasets were obtained from the Gene Expression Omnibus (GEO) database. A total of 1793 immune-related genes were acquired from the Immunology Database and Analysis Portal (ImmPort). Weighted gene co-expression network analysis (WGCNA) was performed for GSE142025, and the red and turquoise co-expression modules were found to be key for DN progression. We utilized four machine learning algorithms, namely, random forest (RF), support vector machine (SVM), adaptive boosting (AdaBoost), and k-nearest neighbor (KNN), to evaluate the diagnostic value of hub genes. Immune infiltration patterns were analyzed using the CIBERSORT algorithm, and the correlation between immune cell type abundance and hub gene expression was also investigated. A total of 77 immune-related genes of advanced DN were selected for subsequent analyzes. Functional enrichment analysis showed that the regulation of cytokine-cytokine receptor interactions and immune cell function play a corresponding role in the progression of DN. The final 10 hub genes were identified through multiple datasets. In addition, the expression levels of the identified hub genes were corroborated through a rat model. The RF model exhibited the highest AUC. CIBERSORT analysis and single-cell sequencing analysis revealed changes in immune infiltration patterns between control subjects and DN patients. Several potential drugs to reverse the altered hub genes were identified through the Drug-Gene Interaction database (DGIdb). This pioneering work provided a novel immunological perspective on the progression of DN, identifying key immune-related genes and potential drug targets, thus stimulating future mechanistic research and therapeutic target identification for DN.

A multimodal atlas of tumour metabolism reveals the architecture of gene–metabolite covariation

Tumour metabolism is controlled by coordinated changes in metabolite abundance and gene expression, but simultaneous quantification of metabolites and transcripts in primary tissue is rare. To overcome this limitation and to study gene–metabolite covariation in cancer, we assemble the Cancer Atlas of Metabolic Profiles of metabolomic and transcriptomic data from 988 tumour and control specimens spanning 11 cancer types in published and newly generated datasets. Meta-analysis of the Cancer Atlas of Metabolic Profiles reveals two classes of gene–metabolite covariation that transcend cancer types. The first corresponds to gene–metabolite pairs engaged in direct enzyme–substrate interactions, identifying putative genes controlling metabolite pool sizes. A second class of gene–metabolite covariation represents a small number of hub metabolites, including quinolinate and nicotinamide adenine dinucleotide, which correlate to many genes specifically expressed in immune cell populations. These results provide evidence that gene–metabolite covariation in cellularly heterogeneous tissue arises, in part, from both mechanistic interactions between genes and metabolites, and from remodelling of the bulk metabolome in specific immune microenvironments.

ELUCIDATING LOCAL PHOSPHODIESTERASE 3A SIGNALING AS A BASIS FOR GAINING INSIGHT INTO HYPERTENSION-DRIVING MECHANISMS

Objective: Mutant PDE3A causes hypertension by driving mechanisms that increase peripheral vascular resistance. However, the media to lumen ratio of vessels in mutant PDE3A rat models varied between second-order mesenteric arteries and thoracic aorta. This observation may be related to alterations of the mutant PDE3A in its intracellular location, its hyperactivity and aberrant phosphorylation, which could lead to altered compartmentalized cAMP signaling. PDE3A hydrolyzes cAMP. Therefore, we hypothesized that alterations in compartmentalized cAMP signaling in vascular smooth muscle cells (VSMC) contributes to the hypertension. Design and method: Three different VSMC models were established: VSMCs from rat thoracic aorta, VSMCs from rat secondary mesenteric arteries and VSMCs expressing mutant PDE3A that were differentiated from human induced pluripotent stem cells. The expression levels of PDE3A and candidate genes were detected by immunofluorescence microscopy, Western blotting and qPCR based on results of RNA sequencing. cAMP and Ca2+ signaling pathways are being evaluated by FRET technology and Ca2+ imaging. Results: VSMCs differentiated from human induced pluripotent stem cells could detect abundant expression of vascular smooth muscle cell markers. Differential expression levels of PDE3A and the two screened candidate genes were found in different types of VSMCs. Conclusions: Elucidating differences in cAMP and Ca2+ cycling between different types of VSMCs yielded new insight into the mechanisms of hypertension. The mutant PDE3A signaling may be a starting point for an innovative, PDE3A compartment-specific pharmacological concept for the treatment of hypertension.

Microglia NLRP3 Inflammasome and Neuroimmune Signaling in Substance Use Disorders

During the last decade, substance use disorders (SUDs) have been increasingly recognized as neuroinflammation-related brain diseases. Various types of abused drugs (cocaine, methamphetamine, alcohol, opiate-like drugs, marijuana, etc.) can modulate the activation status of microglia and neuroinflammation levels which are involved in the pathogenesis of SUDs. Several neuroimmune signaling pathways, including TLR/NF-кB, reactive oxygen species, mitochondria dysfunction, as well as autophagy defection, etc., have been implicated in promoting SUDs. Recently, inflammasome-mediated signaling has been identified as playing critical roles in the microglia activation induced by abused drugs. Among the family of inflammasomes, NOD-, LRR-, and pyrin-domain-containing protein 3 (NLRP3) serves the primary research target due to its abundant expression in microglia. NLRP3 has the capability of integrating multiple external and internal inputs and coordinately determining the intensity of microglia activation under various pathological conditions. Here, we summarize the effects of abused drugs on NLRP3 inflammasomes, as well as others, if any. The research on this topic is still at an infant stage; however, the readily available findings suggest that NLRP3 inflammasome could be a common downstream effector stimulated by various types of abused drugs and play critical roles in determining abused-drug-mediated biological effects through enhancing glia–neuron communications. NLRP3 inflammasome might serve as a novel target for ameliorating the development of SUDs.

IL-17A induces valvular endothelial inflammation and aggravates calcific aortic valve disease

Calcific aortic valve disease (CAVD) is an aging related disease characterized by inflammation and fibrocalcific remodeling. IL-17A is a key cytokine associated with pathophysiology of inflammatory and fibrotic disease. Previous studies showed accumulation of IL-17A-producing T helper lymphocytes in human calcified aortic valves and significantly elevated IL-17RA expression in calcified valves. However, the role of IL-17A signaling in the initiation and development of CAVD is still unclear. In this study, by analyzing public transcriptome databases, we found that IL-17A-IL-17RA signaling is activated in calcified valves. Gene expression analysis revealed significantly increased IL-17A, IL-17RA, and RUNX2 expression in calcified human aortic valves compared to in non-calcified valves, and the expression of IL-17A and IL-17RA were positively correlated with RUNX2 expression. A 5/6 nephrectomy was performed in Apoe−/− (Apoe knockout) mice to establish a CAVD mouse model. IL-17A-neutralizing antibodies significantly reduced valve calcium deposition and decreased expression of RUNX2 in aortic valves. Immunofluorescence staining of human aortic valves and qRT-PCR analysis of primary aortic valve cells revealed abundant expression of IL-17RA in valvular endothelial cells (VECs). RNA sequencing indicated that IL-17A promoted the activation of inflammatory signaling pathways in VECs. Furthermore, qRT-PCR and cytometric bead array analysis confirmed that IL-17A promoted the expression or secretion of inflammatory cytokines IL-6 and IL-1β, chemokines CXCL2 and CXCL8, and fibrosis-related gene COL16A1. Our findings indicate that elevated IL-17A in CAVD may promote valve inflammation, fibrosis, and calcification by inducing endothelial activation and inflammation. Targeting IL-17A-IL-17RA signaling may be a potential therapeutic strategy for CAVD.

Tau polarizes an aging transcriptional signature to excitatory neurons and glia.

Aging is a major risk factor for Alzheimer's disease (AD), and cell-type vulnerability underlies its characteristic clinical manifestations. We have performed longitudinal, single-cell RNA-sequencing in Drosophila with pan-neuronal expression of human tau, which forms AD neurofibrillary tangle pathology. Whereas tau- and aging-induced gene expression strongly overlap (93%), they differ in the affected cell types. In contrast to the broad impact of aging, tau-triggered changes are strongly polarized to excitatory neurons and glia. Further, tau can either activate or suppress innate immune gene expression signatures in a cell-type-specific manner. Integration of cellular abundance and gene expression pinpoints nuclear factor kappa B signaling in neurons as a marker for cellular vulnerability. We also highlight the conservation of cell-type-specific transcriptional patterns between Drosophila and human postmortem brain tissue. Overall, our results create a resource for dissection of dynamic, age-dependent gene expression changes at cellular resolution in a genetically tractable model of tauopathy.