Neudesin as a unique secreted protein with multi-functional roles in neural functions, energy metabolism, and tumorigenesis

Neuron-derived neurotrophic factor promotes the differentiation of intramuscular and subcutaneous adipocytes in goat

Adipocyte play an important role in human health and meat quality by influencing the tenderness, flavor, and juiciness of mutton It has been shown that neuron-derived neurotrophic factor (NENF) is closely related to energy metabolism and adipocyte differentiation in bovine. However, the role of NENF in the goats remains unclear. The aim of this study was to detect the expression of NENF in goat subcutaneous and intramuscular adipocytes, temporal expression profiles of the NENF, and overexpressed NENF on the differentiation of different adipocytes. In this study, PCR amplification successfully cloned the goat NENF gene with a fragment length of 521 bp. In addition, the time point of highest expression of NENF differed between these two adipocytes differentiation processes. Overexpression of NENF in intramuscular and subcutaneous adipocytes promoted the expression levels of differentiation markers CEBPβ and SREBP, which in turn promoted the differentiation of intramuscular and subcutaneous adipocytes. This study will provide basic data for further study of the role of goats in goat adipocyte differentiation and for the final elucidation of its molecular mechanisms in regulating goat adipocyte deposition.

Probing the metalloproteome: an 8-mercaptoquinoline motif enriches minichromosome maintenance complex components as significant metalloprotein targets in live cells

Affinity-based probes are valuable tools for detecting binding interactions between small molecules and proteins in complex biological environments. Metalloproteins are a class of therapeutically significant biomolecules which bind metal ions as part of key structural or catalytic domains and are compelling targets for study. However, there is currently a limited range of chemical tools suitable for profiling the metalloproteome. Here, we describe the preparation and application of a novel, photoactivatable affinity-based probe for detection of a subset of previously challenging to engage metalloproteins. The probe, bearing an 8-mercaptoquinoline metal chelator, was anticipated to engage several zinc metalloproteins, including the 26S-proteasome subunit Rpn11. Upon translation of the labelling experiment to mammalian cell lysate and live cell experiments, proteomic analysis revealed that several metalloproteins were competitively enriched. The diazirine probe SMK-24 was found to effectively enrich multiple components of the minichromosome maintenance complex, a zinc metalloprotein assembly with helicase activity essential to DNA replication. Cell cycle analysis experiments revealed that HEK293 cells treated with SMK-24 experienced stalling in G0/G1 phase, consistent with inactivation of the DNA helicase complex. This work represents an important contribution to the library of cell-permeable chemical tools for studying a collection of metalloproteins for which no previous probe existed.

A secretory protein neudesin regulates splenic red pulp macrophages in erythrophagocytosis and iron recycling

Neudesin, originally identified as a neurotrophic factor, has primarily been studied for its neural functions despite its widespread expression. Using 8-week-old neudesin knockout mice, we elucidated the role of neudesin in the spleen. The absence of neudesin caused mild splenomegaly, shortened lifespan of circulating erythrocytes, and abnormal recovery from phenylhydrazine-induced acute anemia. Blood cross-transfusion and splenectomy experiments revealed that the shortened lifespan of erythrocytes was attributable to splenic impairment. Further analysis revealed increased erythrophagocytosis and decreased iron stores in the splenic red pulp, which was linked to the upregulation of Fcγ receptors and iron-recycling genes in neudesin-deficient macrophages. In vitro analysis confirmed that neudesin suppressed erythrophagocytosis and expression of Fcγ receptors through ERK1/2 activation in heme-stimulated macrophages. Finally, we observed that 24-week-old neudesin knockout mice exhibited severe symptoms of anemia. Collectively, our results suggest that neudesin regulates the function of red pulp macrophages and contributes to erythrocyte and iron homeostasis.

Cytoplasmic Shotgun Proteomic Points to Key Proteins and Pathways in Temozolomide-Resistant Glioblastoma Multiforme

Temozolomide (TMZ) is the first line of chemotherapy to treat primary brain tumors of the type glioblastoma multiforme (GBM). TMZ resistance (TMZR) is one of the main barriers to successful treatment and is a principal factor in relapse, resulting in a poor median survival of 15 months. The present paper focuses on proteomic analyses of cytosolic fractions from TMZ-resistant (TMZR) LN-18 cells. The experimental workflow includes an easy, cost-effective, and reproducible method to isolate subcellular fraction of cytosolic (CYTO) proteins, mitochondria, and plasma membrane proteins for proteomic studies. For this study, enriched cytoplasmic fractions were analyzed in replicates by nanoflow liquid chromatography tandem high-resolution mass spectrometry (nLC-MS/MS), and proteins identified were quantified using a label-free approach (LFQ). Statistical analysis of control (CTRL) and temozolomide-resistant (TMZR) proteomes revealed proteins that appear to be differentially controlled in the cytoplasm. The functions of these proteins are discussed as well as their roles in other cancers and TMZ resistance in GBM. Key proteins are also described through biological processes related to gene ontology (GO), molecular functions, and cellular components. For protein-protein interactions (PPI), network and pathway involvement analyses have been performed, highlighting the roles of key proteins in the TMZ resistance phenotypes. This study provides a detailed insight into methods of subcellular fractionation for proteomic analysis of TMZ-resistant GBM cells and the potential to apply this approach to future large-scale studies. Several key proteins, protein-protein interactions (PPI), and pathways have been identified, underlying the TMZ resistance phenotype and highlighting the proteins' biological functions.

The level of the neudesin in type-2 diabetic patients and the relationship between the metabolic parameters and carotid intima-media thickness

BACKGROUND

Neudesin is a protein that is secreted from adipose tissue and central nervous system and has a regulatory function on energy metabolism. Although the effect of this protein is shown in the experimental model of type-2 diabetes mellitus (type-2DM), its effect in humans is not clearly known. In this study, we aimed to evaluate the relationship between serum neudesin level and metabolic, anthropometric and cardiovascular parameters in newly diagnosed type-2DM patients (group 1).

METHODS

Forty patients in each were included in our study for group 1 and for the control group (group 2), which consisted of age and sex-matched healthy subjects. Serum neudesin, hs-CRP, carotid intima media thickness (CIMT), Body Mass Index (BMI) and insulin resistance (HOMA-IR) levels were compared prospectively.

RESULTS

Serum neudesin levels were significantly higher in diabetic patients than in the control group (type-2DM: 64.69±3.06 ng/mL, control: 55.52±5.48 ng/mL, P=0.004*). There was an independent relationship between serum neudesin and HOMA-IR and BMI. Although there is a correlation between serum neudesin and CIMT; this feature disappeared in the regression analysis.

CONCLUSIONS

Serum neudesin increased in new diagnosis type-2DM patients. This increase seems to be related to obesity and insulin resistance. However, more extensive research is needed to clarify this issue.

Single-cell RNA sequencing depicts metabolic changes in children with aplastic anemia

Introduction

Aplastic anemia (AA) is a bone marrow hematopoietic failure syndrome mediated by immune cells. The mechanism of this immune disorder is not well understood and therapeutic strategies still need to be improved.

Methods

Studies have found that abnormalities in metabolisms promote the survival of AA cells. In recent years, an increasing number of studies have reported the immunosuppressive therapy for the treatment of AA. In this study, we analyzed the transcriptome of AA from peripheral blood compared with healthy donors by single-cell sequencing and identified the affected metabolic pathways including lysine degradation. We demonstrated that the metabolic abnormalities of T lymphocytes mainly focus on glycolysis/gluconeogenesis. In addition, the metabolic abnormalities of natural killer cells concentrated in oxidative phosphorylation.

Results

The key genes involved in abnormal metabolic processes were Neustein neurotrophic factor (NENF), inositol polyphosphate-4-phosphatase type II B (INPP4B), aldo-keto reductase family 1, member C3 (AKR1C3), and carbohydrate (N-acetylglucosamine-6-O) sulfotransferase 2 (CHST2) by differential gene expression analysis.

Discussion

Molecule interaction analysis showed that tumor necrosis factor superfamily, member 12 (TNFSM12) in tumor necrosis factor (TNF) signaling was broadly activated in AA. In conclusion, we suppose that the treatment of the immune cells’ abnormal metabolic pathway may contribute to the development of novel strategies to treat AA.

Increased levels of plasma neudesin in adult growth hormone deficiency and their relationship with plasma liver-expressed antimicrobial peptide-2 levels: a cross-sectional study

PURPOSE

Adult growth hormone deficiency (aGHD) is characterized by an altered metabolic profile and increased cardiovascular risk. Neudesin is a newly discovered protein mainly secreted from adipose tissue and brain, under evaluation for its possible activity as a negative regulator of energy expenditure. Liver-expressed antimicrobial peptide (LEAP)-2 is a competitive antagonist of ghrelin on its receptor. An observational cross-sectional study was performed to test the hypothesis that plasma neudesin levels may be modified in aGHD. Given the role played in the energy balance, any possible relationships between neudesin, LEAP-2 and metabolic and anthropometric parameters were evaluated.

SUBJECTS AND METHODS

Thirty-eight patients were included: 18 aGHD patients (7 females and 11 males, aged 59.7 ± 2.6 years, BMI 30.2 ± 2.2 kg/m²); 20 healthy controls (12 females and 8 males, aged 47.1 ± 2.5 years, BMI 24.1 ± 0.9 kg/m²). All patients were evaluated for glucose, insulin, HOMA and QUICKI index, total/LDL/HDL cholesterol, triglycerides, uric acid, and IGF-1. Plasma neudesin, LEAP-2, and ghrelin were measured by ELISA. Fat mass was evaluated by DEXA.

RESULTS

Neudesin levels were significantly higher in aGHD versus controls. We confirmed the finding of significantly lower ghrelin levels and significantly higher LEAP-2/ghrelin ratio in aGHD patients and found a significant direct correlation between neudesin and LEAP-2 levels. A significant direct correlation between neudesin and fat mass percentage was found in the whole population.

CONCLUSION

These results suggest the onset of adaptive responses to an altered metabolic picture in aGHD. The changes in two distinct pathways that modulate food intake and the still limited knowledge about neudesin suggest future developments in this field.

Many or too many progesterone membrane receptors? Clinical implications

Several receptors for nongenomically initiated actions of progesterone (P4) exist, namely membrane-associated P4 receptors (MAPRs), membrane progestin receptors (mPRs), receptors for neurosteroids [GABA_A receptor (GABA_AR), NMDA receptor, sigma-1 and -2 receptors (S1R/S2R)], the classical genomic P4 receptor (PGR), and α/β hydrolase domain-containing protein 2 (ABHD2). Two drugs related to this field have been approved: brexanolone (Zulresso™) for the treatment of postpartum depression, and ganaxolone (Ztalmy™) for the treatment of CDKL5 deficiency disorder. Both are derivatives of P4 and target the GABA_AR. Several other indications are in clinical testing. CT1812 (Elayta™) is also being tested for the treatment of Alzheimer's disease (AD) in Phase 2 clinical trials, targeting the P4 receptor membrane component 1 (PGRMC1)/S2R complex. In this Review, we highlight emerging knowledge on the mechanisms of nongenomically initiated actions of P4 and its derivatives.

The assessment of maternal and umbilical cord neudesin levels in pregnancies with gestational diabetes mellitus

Gestational diabetes mellitus (GDM) occurs due to the inability to adapt to physiologically observed changes in carbohydrate metabolism during pregnancy. Neudesin is a multi-functional secreted protein suggested to have a crucial regulator role in energy and carbohydrate metabolism. This study aimed to evaluate maternal serum and umbilical cord neudesin levels in pregnancies with GDM. Twenty-four singleton pregnancies with GDM were compared with gestational age-matched 23 uncomplicated pregnancies in this cross-sectional study. In comparison to the control group, significantly higher maternal serum and umbilical cord neudesin levels were observed in pregnancies with GDM (p < .001). Maternal serum and umbilical cord neudesin levels were also significantly positively correlated with maternal serum insulin levels and HOMA-IR values in the study group (p < .001). Neudesin, with its regulator role in carbohydrate metabolism, may be a contributing factor in the pathophysiology of GDM and may be a target of strategies for the prevention and treatment of GDM.Impact statementWhat is already known on this subject? Progressive changes in carbohydrate metabolism occur in normal pregnancy to provide continuous nutritional supply to the developing foetus and pregnant woman. When these progressive metabolic changes cannot be compensated, gestational diabetes mellitus (GDM) occurs.What the results of this study add? This is the first study to provide information about maternal serum and umbilical cord neudesin levels in pregnancies with GDM. This study observed that the serum levels of neudesin, which is suggested to have a regulator role in carbohydrate metabolism, were increased in pregnant women with GDM.What the implications are of these findings for clinical practice and/or future research? Neudesin may contribute to impaired carbohydrate metabolism in pregnancies with GDM and can be the subject of further studies on the prevention and treatment of GDM.

Pleiotropic Actions of PGRMC Proteins in Cancer

Progesterone receptor membrane component (PGRMC) proteins play important roles in tumor growth, progression, and chemoresistance, of which PGRMC1 is the best characterized. The ancestral member predates the evolution of metazoans, so it is perhaps not surprising that many of the purported actions of PGRMC proteins are rooted in fundamental metabolic processes such as proliferation, apoptosis, and DNA damage responses. Despite mediating some of the actions of progesterone (P4) and being fundamentally required for female fertility, PGRMC1 and PGRMC2 are broadly expressed in most tissues. As such, these proteins likely have both progesterone-dependent and progesterone-independent functions. It has been proposed that PGRMC1 acquired the ability to mediate P4 actions over evolutionary time through acquisition of its cytochrome b5-like heme/sterol-binding domain. Diverse reproductive and nonreproductive diseases associate with altered PGRMC1 expression, epigenetic regulation, or gene silencing mechanisms, some of which include polycystic ovarian disease, premature ovarian insufficiency, endometriosis, Alzheimer disease, and cancer. Although many studies have been completed using transformed cell lines in culture or in xenograft tumor approaches, recently developed transgenic model organisms are offering new insights in the physiological actions of PGRMC proteins, as well as pathophysiological and oncogenic consequences when PGRMC expression is altered. The purpose of this mini-review is to provide an overview of PGRMC proteins in cancer and to offer discussion of where this field must go to solidify PGRMC proteins as central contributors to the oncogenic process.

Serum Neudesin Levels in Obese Adolescents

OBJECTIVE

Advances in knowledge of neurotrophic factors are now revealing the complex control of energy homeostasis and appetite, as well as the crucial role these factors play in nervous system function. The aim of this study was to assess serum levels of neudesin in adolescents with obesity and to examine the relationship between these levels and metabolic outcomes.

METHODS

Adolescents, aged 10-17 years were enrolled. Subjects were divided into normal weight, obese and morbidly obese subgroups. Serum neudesin concentrations were compared between the groups.

RESULTS

In total, 88 adolescents were recruited, of whom 30 (34.1%) were normal weight, 15 (17.0%) were obese and 43 (48.9%) were morbidly obese. Neudesin levels were significantly lower in obese adolescents than in the control group (p=0.013). A correlation analysis applied to the whole study group revealed a negative correlation between serum neudesin concentration and body mass index (BMI) z scores (r=-0.40, p<0.001). Serum neudesin levels tended to increase in adolescents with metabolic syndrome, insulin resistance, dyslipidaemia, and hypertension but the differences were not significant (p=0.259, p=0.246, p=0.259, and p=0.523, respectively).

CONCLUSION

Serum neudesin levels were significantly correlated with BMI z score in obese adolescents. Generally, serum neudesin levels were low in obese and morbidly obese adolescents and tended to increase with the appearance of metabolic disorders. Both obesity and associated metabolic disorders have multifactorial causes. Therefore, we suggest that the role of the neudesin molecule in the regulatory mechanisms of obesity and metabolic disorders should be further investigated with well-designed studies enrolling larger groups.

Review of Novel Potential Insulin Resistance Biomarkers in PCOS Patients—The Debate Is Still Open

Research on proteins and peptides that play roles in metabolic regulation, which may be considered potential insulin resistance markers in some medical conditions, such as diabetes mellitus, obesity and polycystic ovarian syndrome (PCOS), has recently gained in interest. PCOS is a common endocrine disorder associated with hyperandrogenemia and failure of ovulation, which is often accompanied by metabolic abnormalities, including obesity, dyslipidemia, hyperinsulinemia, and insulin resistance. In this review, we focus on less commonly known peptides/proteins and investigate their role as potential biomarkers for insulin resistance in females affected by PCOS. We summarize studies comparing the serum fasting concentration of particular agents in PCOS individuals and healthy controls. Based on our analysis, we propose that, in the majority of studies, the levels of nesfastin-1, myonectin, omentin, neudesin were decreased in PCOS patients, while the levels of the other considered agents (e.g., preptin, gremlin-1, neuregulin-4, xenopsin-related peptide, xenin-25, and galectin-3) were increased. However, there also exist studies presenting contrary results; in particular, most data existing for lipocalin-2 are inconsistent. Therefore, further research is required to confirm those hypotheses, as well as to elucidate the involvement of these factors in PCOS-related metabolic complications.

Testicular Hypoplasia with Normal Fertility in Neudesin-Knockout Mice

Neudesin is a secretory protein involved in the brain development during embryonic period and diet-induced development of adipose tissue. Although neudesin is also expressed in the testis, its physiological functions in the testis have not been documented. Therefore, we examined neudesin-encoding neuron-derived neurotrophic factor (Nenf) gene-knockout (Neudesin-KO) mice to clarify the functions of neudesin in the testis. The testicular size of the Neudesin-KO mice was significantly smaller than that of wild-type (WT) mice. However, histological analyses did not reveal any abnormalities in the testis, caput epididymis, and cauda epididymis. Sperm number in the cauda epididymis was comparable between WT and KO mice. Neudesin-KO male mice produced vaginal plugs on paired WT female mice, with a frequency similar to that in WT male mice. A similar number of embryos were developed in the females copulated with WT and Neudesin-KO males. Molecular analysis indicated that the ion transporters Slc19a1 and Kcnk3 were more expressed in the testis of Neudesin-KO mice than in the testis of WT mice, suggesting that the transport of ions and some nutrients in the testis has some abnormalities. Testicular size decreased on postnatal day 6, but not on the day of birth, indicating that neudesin is involved in the postnatal, but not embryonic, development of testis. These results indicate a novel role of neudesin in the development of testis.

Plasma Levels of Neudesin and Glucose Metabolism in Obese and Overweight Children

Childhood overweight and obesity are among the major health problems of modern times, especially in Western countries, due to their association with increased cardiovascular and cancer risk in adulthood. Neudesin, a recently discovered peptide secreted mainly in the brain and adipose tissue, is being investigated for its possible activity as a negative regulator of energy expenditure. We conducted a cross-sectional observational preliminary study with the aim of testing the hypothesis that plasma levels of neudesin can be modified in obese and overweight children and to evaluate any possible relationship between plasma neudesin levels and metabolic and anthropometric parameters. 34 Children (Tanner's stage 1) were included and divided in two groups according to Cole's criteria. Group A included obese and overweight children (23 patients, 17 females and 6 males, aged 4-10 years); Group B included healthy normal-weight children (11 subjects, 7 females and 4 males, aged 3-10 years). Metabolic (glucose and insulin, total, LDL- and HDL-cholesterol, triglycerides, uric acid) and hormonal (fT3, fT4, TSH, IGF-1, leptin) parameters were evaluated. HOMA-IR and QUICKI index and the area under the curve (AUC) of glucose and insulin after oral glucose load were calculated in obese and overweight children. Neudesin was measured by ELISA. Neudesin levels were significantly higher in obese/overweight children than in controls. In obese and overweight children, plasma neudesin levels were significantly directly correlated with blood glucose and glucose AUC. Taken together, these results, although preliminary, may suggest a possible age-related role of neudesin in glucose homeostasis in obese/overweight children.

Nutritional reprogramming of mouse liver proteome is dampened by metformin, resveratrol, and rapamycin

Nutrient sensing pathways influence metabolic health and aging, offering the possibility that diet might be used therapeutically, alone or with drugs targeting these pathways. We used the Geometric Framework for Nutrition to study interactive and comparative effects of diet and drugs on the hepatic proteome in mice across 40 dietary treatments differing in macronutrient ratios, energy density, and drug treatment (metformin, rapamycin, resveratrol). There was a strong negative correlation between dietary energy and the spliceosome and a strong positive correlation between dietary protein and mitochondria, generating oxidative stress at high protein intake. Metformin, rapamycin, and resveratrol had lesser effects than and dampened responses to diet. Rapamycin and metformin reduced mitochondrial responses to dietary protein while the effects of carbohydrates and fat were downregulated by resveratrol. Dietary composition has a powerful impact on the hepatic proteome, not just on metabolic pathways but fundamental processes such as mitochondrial function and RNA splicing.

Molecular Characterization of Membrane Steroid Receptors in Hormone-Sensitive Cancers

Cancer is one of the most common causes of death worldwide, and its development is a result of the complex interaction of genetic factors, environmental cues, and aging. Hormone-sensitive cancers depend on the action of one or more hormones for their development and progression. Sex steroids and corticosteroids can regulate different physiological functions, including metabolism, growth, and proliferation, through their interaction with specific nuclear receptors, that can transcriptionally regulate target genes via their genomic actions. Therefore, interference with hormones’ activities, e.g., deregulation of their production and downstream pathways or the exposition to exogenous hormone-active substances such as endocrine-disrupting chemicals (EDCs), can affect the regulation of their correlated pathways and trigger the neoplastic transformation. Although nuclear receptors account for most hormone-related biologic effects and their slow genomic responses are well-studied, less-known membrane receptors are emerging for their ability to mediate steroid hormones effects through the activation of rapid non-genomic responses also involved in the development of hormone-sensitive cancers. This review aims to collect pre-clinical and clinical data on these extranuclear receptors not only to draw attention to their emerging role in cancer development and progression but also to highlight their dual role as tumor microenvironment players and potential candidate drug targets.

Neudesin: a neuropeptide hormone decreased in subjects with polycystic ovary syndrome

Neudesin is a neuropeptide hormone involves in female reproduction system via promoting effects of progesterone. Polycystic ovary syndrome (PCOS) is a metabolic and reproductive disorder associated with hypothalamic-pituitary-ovarian axis abnormalities and impaired negative feedback mechanism of progesterone upon gonadotropin-releasing hormone secretion. Our aims were to discover whether neudesin levels were altered in PCOS women comparing to controls and to determine the link of neudesin with hormonal-metabolic parameters in PCOS women. The current research was designed as a case-control study. Sixty-eight subjects with PCOS and 67 age- and body mass index (BMI)-matched subjects as controls were enrolled into the study. Circulating neudesin levels were measured by ELISA. Neudesin levels were significantly lower in PCOS subjects compared to controls (4.07 ± 1.22 vs. 6.02 ± 2.07 ng/ml, p < .001). Neudesin exhibited an inversely independent link with luteinizing hormone, free-androgen index, and BMI whereas it showed a positively independent link with progesterone in women with PCOS. Logistic regression analysis revealed that decreased neudesin levels were parallel with increased risk of having PCOS. Decreased neudesin levels were associated with hormonal disturbances in PCOS women, suggesting that neudesin may play a role in pathophysiology of PCOS.

Early eukaryotic origins and metazoan elaboration of MAPR family proteins

The membrane-associated progesterone receptor (MAPR) family consists of heme-binding proteins containing a cytochrome b₅ (cytb₅) domain characterized by the presence of a MAPR-specific interhelical insert region (MIHIR) between helices 3 and 4 of the canonical cytb5-domain fold. Animals possess three MAPR genes (PGRMC-like, Neuferricin and Neudesin). Here we show that all three animal MAPR genes were already present in the common ancestor of the opisthokonts (comprising animals and fungi as well as related single-celled taxa). All three MAPR genes acquired extensions C-terminal to the cytb₅ domain, either before or with the evolution of animals. The archetypical MAPR protein, progesterone receptor membrane component 1 (PGRMC1), contains phosphorylated tyrosines Y139 and Y180. The combination of Y139/Y180 appeared in the common ancestor of cnidarians and bilaterians, along with an early embryological organizer and synapsed neurons, and is strongly conserved in all bilaterian animals. A predicted protein interaction motif in the PGRMC1 MIHIR is potentially regulated by Y139 phosphorylation. A multilayered model of animal MAPR function acquisition includes some pre-metazoan functions (e.g., heme binding and cytochrome P450 interactions) and some acquired animal-specific functions that involve regulation of strongly conserved protein interaction motifs acquired by animals (Metazoa). This study provides a conceptual framework for future studies, against which especially PGRMC1's multiple functions can perhaps be stratified and functionally dissected.

Neudesin Neurotrophic Factor Promotes Bovine Preadipocyte Differentiation and Inhibits Myoblast Myogenesis

Simple Summary

Neudesin neurotrophic factor (NENF) is a secreted protein that was significantly inhibited in the fat-muscle co-culture system in our previous study. However, studies on NENF regulation of bovine muscle development and involvement in the cross-talk between adipose tissue and skeletal muscle have not been reported. Hence, the aim of this study was to clarify the roles of NENF in bovine myoblast and preadipocyte differentiation. In this study, we first examined the spatial expression patterns of NENF in different tissues and found that NENF was highly expressed in the muscle of four-day-old and 24-month-old Qinchuan cattle. Compared with 4-day-old Qinchuan cattle, the expression level of NENF was significantly up-regulated in 24-month-old bovine adipose tissue. Then, we detected the expression pattern of the NENF gene in bovine preadipocyte and myoblast differentiation and found that the expression of NENF mRNA peaks at day 6 during preadipocyte differentiation and peaks at day 4 during myoblast differentiation. Furthermore, we found that the endogenous knockdown of NENF inhibited the differentiation of preadipocytes and promoted the differentiation of myoblasts. These findings not only lay the foundation for the construction of regulatory pathways during fat and muscle differentiation but also provide a theoretical basis for molecular breeding of beef cattle.

Abstract

Neudesin neurotrophic factor (NENF) is a secreted protein that is essential in multiple biological processes, including neural functions, adipogenesis, and tumorigenesis. In our previous study, NENF was significantly inhibited in the bovine adipocytes-myoblasts co-culture system. However, studies on NENF regulation of bovine muscle development and involvement in the cross-talk between adipose tissue and skeletal muscle have not been reported. Hence, the aim of this study was to clarify the functional roles of NENF in bovine preadipocytes and myoblasts. Real-time quantitative PCR (RT-qPCR) was performed to examine the spatial expression patterns of NENF in different tissues, and the results showed that NENF was highly expressed in the muscle of four-day-old and 24-month-old Qinchuan cattle. Compared with four-day-old Qinchuan cattle, the expression level of NENF was significantly up-regulated in 24-month-old bovine adipose tissue. To explore the roles of NENF in bovine myoblast and preadipocyte differentiation, small interfering RNA (siRNA) targeting the NENF gene were transfected into bovine preadipocytes and myoblasts to knock down the expression of the NENF gene. The results showed that the knockdown of NENF in differentiating adipocytes attenuated lipid accumulation, decreased the mRNA expression of adipogenic key marker genes PPARγ, CEBPα, CEBPβ, FASN, and SCD1, and decreased the protein expression of PPARγ, CEBPα, and FASN. The formation of myotubes was significantly accelerated, and the mRNA expression levels of myogenic marker genes MYOD1, MYF5, MYF6, MEF2A, MEF2C, and CKM, and the protein expression levels of MYOD1, MYF6, MEF2A, and CKM were up-regulated in myoblasts where NENF was knocked down. In short, the knockdown of NENF inhibited preadipocyte differentiation and promoted myoblast myogenesis.

Serum and cerebrospinal fluid Neudesin concentration and Neudesin Quotient as potential circulating biomarkers of a primary brain tumor

Background

Despite the previously suggested role of Neudesin in tumorigenesis and its potential as a novel target for the treatment of cancers, its prognostic value has never been examined. Thus, the aim of the study was to evaluate Neudesin concentrations in primary brain tumor patients and make a comparison with non-tumoral individuals.

Methods

Cerebrospinal fluid (CSF) and serum Neudesin concentration was evaluated by means of the ELISA method.

Results

The total group of brain tumor patients had statistically lower serum Neudesin concentrations compared to the non-tumoral group (P = 0.037). The meningeal tumor subgroup also had statistically lower serum Neudesin concentrations compared to the non-tumoral group (P = 0.012). The Astrocytic brain tumor subgroup had significantly higher CSF Neudesin concentrations compared to the non-tumoral group (P = 0.046). Neudesin Quotient (CSF concentration divided by serum concentration) in the astrocytic brain tumor subgroup was statistically higher compared to the non-tumoral group (P = 0.023). Males had statistically lower concentrations of the serum Neudesin compared to females (P = 0.047). Univariate linear regression analysis revealed that for women the serum Neudesin concentration was 1.53 times higher than for men. In the model of multivariate linear regression analysis, predictor variables influencing serum Neudesin concentrations included CSF Neudesin concentration and the Neudesin Quotient, if other model parameters are fixed. The developed model explains 82% of the variance in serum Neudesin concentration. Both linear regression models, univariate and multivariate, pointed to fewer factors with a potential to influence the Neudesin Quotient compared to serum Neudesin concentration.

Conclusions

In astrocytic brain tumor patients Neudesin concentrations within the cerebrospinal fluid are higher compared with non-tumoral individuals. Serum Neudesin concentration strongly correlates with its CSF level. In primary brain tumor patients serum Neudesin concentration is clearly gender-dependent. Linear regression models pointed to fewer factors that may influence the Neudesin Quotient value, which suggests it is a better biomarker of astrocytic brain tumors than serum and CSF Neudesin concentrations alone.

Neudesin in obesity and type 2 diabetes mellitus: the effect of acute fasting and weight reducing interventions

CONTEXT

Neudesin has recently been identified as a novel regulator of energy expenditure in experimental animals; however, its role in humans remains unexplored.

OBJECTIVE

The aim of this study was to assess the effects of obesity and type 2 diabetes mellitus (T2DM) along with selected weight reducing interventions on serum neudesin levels and adipose tissue mRNA expression.

PATIENTS AND METHODS

Fifteen obese subjects with T2DM undergoing endoscopic duodenal-jejunal bypass liner (DJBL) implantation, 17 obese subjects (11 with T2DM, 6 without T2DM) scheduled for gastric plication (GP), 15 subjects with functional hypoglycemia subjected to 72-hour acute fasting (AF), and 12 healthy controls were included in the study.

RESULTS

Baseline neudesin levels were comparable between all groups. DJBL increased neudesin at 6 and 10 months after the procedure (1.77±0.86 vs 2.28±1.27 vs 2.13±1.02 ng/mL, P=0.001 for baseline vs 6 vs 10 months) along with reduction in body weight and improvement of HbA_1c without any effect on neudesin mRNA expression in subcutaneous adipose tissue. Conversely, GP did not affect neudesin levels despite marked reduction in body weight and improvement of HbA_1c. In contrast, AF decreased neudesin levels during the entire period (1.74±0.54 vs 1.46±0.48 ng/mL, P=0.001 for baseline vs 72 hours) with no impact of subsequent re-alimentation on neudesin concentrations.

CONCLUSION

Neudesin levels are differentially regulated during AF and chronic weight reduction induced by DJBL or GP. Further studies are needed to assess its possible significance in energy homeostasis regulation in humans.

Membrane Associated Progesterone Receptors: Promiscuous Proteins with Pleiotropic Functions - Focus on Interactions with Cytochromes P450

Membrane-associated progesterone receptors (MAPR) are a group of four rather small, partially homologous proteins, which share a similar non-covalent heme-binding domain that is related to cytochrome b5, a well-known functional interaction partner of microsomal cytochrome P450 (CYP) monooxygenase systems. Apart from their structural similarities the four proteins progesterone membrane component 1 (PGRMC1, also referred to as IZA, sigma-2 receptor, Dap1), PGRMC2, neudesin (NENF) and neuferricin (CYB5D2) display surprisingly divergent and multifunctional physiological properties related to cholesterol/steroid biosynthesis, drug metabolism and response, iron homeostasis, heme trafficking, energy metabolism, autophagy, apoptosis, cell cycle regulation, cell migration, neural functions, and tumorigenesis and cancer progression. The purpose of this mini-review is to briefly summarize the structural and functional properties of MAPRs with particular focus on their interactions with the CYP system. For PGRMC1, originally identified as a non-canonical progesterone-binding protein that mediates some immediate non-genomic actions of progesterone, available evidence indicates mainly activating interactions with steroidogenic CYPs including CYP11A1, CYP21A2, CYP17, CYP19, CYP51A1, and CYP61A1, while interactions with drug metabolizing CYPs including CYP2C2, CYP2C8, CYP2C9, CYP2E1, and CYP3A4 were either ineffective or slightly inhibitory. For the other MAPRs the evidence is so far less conclusive. We also point out that experimental limitations question some of the previous conclusions. Use of appropriate model systems should help to further clarify the true impact of these proteins on CYP-mediated metabolic pathways.

The evolutionary appearance of signaling motifs in PGRMC1

A complex PGRMC1-centred regulatory system controls multiple cell functions. Although PGRMC1 is phosphorylated at several positions, we do not understand the mechanisms regulating its function. PGRMC1 is the archetypal member of the membrane associated progesterone receptor (MAPR) family. Phylogentic comparison of MAPR proteins suggests that the ancestral metazoan "PGRMC-like" MAPR gene resembled PGRMC1/PGRMC2, containing the equivalents of PGRMC1 Y139 and Y180 SH2 target motifs. It later acquired a CK2 site with phosphoacceptor at S181. Separate PGRMC1 and PGRMC2 genes with this "PGRMC-like" structure diverged after the separation of vertebrates from protochordates. Terrestrial tetrapods possess a novel proline-rich PGRMC1 SH3 target motif centred on P64 which in mammals is augmented by a phosphoacceptor at PGRMC1 S54, and in primates by an additional S57 CK2 site. All of these phosphoacceptors are phosphorylated in vivo. This study suggests that an increasingly sophisticated system of PGRMC1-modulated multicellular functional regulation has characterised animal evolution since Precambrian times.