EGF-like growth factors upregulate pentraxin 3 expression in human granulosa-lutein cells.

The epidermal growth factor (EGF)-like factors, comprising amphiregulin (AREG), betacellulin (BTC), and epiregulin (EREG), play a critical role in regulating the ovulatory process. Pentraxin 3 (PTX3), an essential ovulatory protein, is necessary for maintaining extracellular matrix (ECM) stability during cumulus expansion. The aim of this study was to investigate the impact of EGF-like factors, AREG, BTC, and EREG on the expression and production of PTX3 in human granulosa-lutein (hGL) cells and the molecular mechanisms involved. Our results demonstrated that AREG, BTC, and EREG could regulate follicular function by upregulating the expression and increasing the production of PTX3 in both primary (obtained from 20 consenting patients undergoing IVF treatment) and immortalized hGL cells. The upregulation of PTX3 expression was primarily facilitated by the activation of the extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling pathway, induced by these EGF-like factors. In addition, we found that the upregulation of PTX3 expression triggered by the EGF-like factors was completely reversed by either pretreatment with the epidermal growth factor receptor (EGFR) inhibitor, AG1478, or knockdown of EGFR, suggesting that EGFR is crucial for activating the ERK1/2 signaling pathway in hGL cells. Overall, our findings indicate that AREG, BTC, and EREG may modulate human cumulus expansion during the periovulatory stage through the upregulation of PTX3.

Blood-based epigenome-wide analyses of chronic low-grade inflammation across diverse population cohorts.

Chronic inflammation is a hallmark of age-related disease states. The effectiveness of inflammatory proteins including C-reactive protein (CRP) in assessing long-term inflammation is hindered by their phasic nature. DNA methylation (DNAm) signatures of CRP may act as more reliable markers of chronic inflammation. We show that inter-individual differences in DNAm capture 50% of the variance in circulating CRP (N = 17,936, Generation Scotland). We develop a series of DNAm predictors of CRP using state-of-the-art algorithms. An elastic-net-regression-based predictor outperformed competing methods and explained 18% of phenotypic variance in the Lothian Birth Cohort of 1936 (LBC1936) cohort, doubling that of existing DNAm predictors. DNAm predictors performed comparably in four additional test cohorts (Avon Longitudinal Study of Parents and Children, Health for Life in Singapore, Southall and Brent Revisited, and LBC1921), including for individuals of diverse genetic ancestry and different age groups. The best-performing predictor surpassed assay-measured CRP and a genetic score in its associations with 26 health outcomes. Our findings forge new avenues for assessing chronic low-grade inflammation in diverse populations.

Tumor necrosis factor alpha induced protein 3, interleukin 10, tumor necrosis factor alpha, and interleukin 17 F genes polymorphisms in Algerian patients with rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic inflammation. Its pathogenesis involves immunological, genetic, and environmental factors. We investigate the association between Tumor Necrosis Factor α Protein 3 (TNFAIP3), Interleukin 10 (IL10), Tumor Necrosis Factor α (TNF α), and Interleukin 17 F (IL17F) polymorphisms with susceptibility to RA. METHODS AND RESULTS: 191 patients with RA diagnosed according to the American College of Rheumatology (ACR)/ European League Against Rheumatism (EULAR) classification and 190 healthy subjects were recruited. Rheumatoid factor (RF), anti-citrullinated peptide antibodies (ACPA), and C-reactive protein (CRP) were measured. Genotyping of the polymorphisms was performed by real-time PCR. Analysis of the allelic frequencies of TNFAIP3 showed a positive association OR (95% CI) = 1.46 (1.01-2.09); p = 0.04, but failed to meet the criteria of significance after Bonferroni Correction. The genotypic and allelic distribution of the IL10, IL17F, and TNFα showed no significant difference when comparing the RA group with controls. Furthermore, the genotype codominant model shows a moderate positive association in the presence of ACPA (OR (95% CI) = 2.82 (1.22-6.24); p = 0.01. None of the polymorphisms studied was associated with RF and CRP production. CONCLUSION: Our results show that there is a tendency for the AG genotype of IL10-1082 to be associated with the production of ACPA in patients with RA. None of the variants studied were associated with RA susceptibility in Algerians.

Inhibition of neuronal pentraxin 2 relieved epileptic seizure via reducing GluA1 phosphorylation.

Neuronal pentraxin 2 (Nptx2), a member of the synaptic protein family linked to excitatory synaptic formation, is found to be upregulated in epileptic mice, yet its role in epilepsy has been unclear. In vivo, we constructed a mouse model of epilepsy by using kainic acid induction. In vitro experiments, a Mg2+-free medium was used to induce epileptiform discharges in neurons. The results showed that the Nptx2 was upregulated in epileptic mice. Moreover, Nptx2 knockdown reduced the number of seizures and seizure duration. Knocking down Nptx2 not only reduced the number and duration of seizures but also showed a decrease in electroencephalogram amplitude. Behavioral tests indicated improvements in learning and memory abilities after Nptx2 knockdown. The Nissl staining and Timms staining revealed that Nptx2 silencing mitigated epilepsy-induced brain damage. The immunofluorescence staining revealed that Nptx2 absence resulted in a reduction of apoptosis. Nptx2 knockdown reduced Bax, cleaved caspase3, and cleaved caspase9 expression, while increased Bcl-2 expression. Notably, Nptx2 knockdown inhibited GluA1 phosphorylation at the S831 site and reduced the GluA1 membrane expression. The PSD95 expression declined in the epilepsy model, while the Nptx2 knockdown reversed it. Collectively, our study indicated that Nptx2 silencing not only alleviated brain damage and neuron apoptosis but also improved learning and memory ability in epileptic mice, suggesting Nptx2 as a promising target for epilepsy treatment.

Methylation patterns associated with C-reactive protein in racially and ethnically diverse populations.

Systemic low-grade inflammation is a feature of chronic disease. C-reactive protein (CRP) is a common biomarker of inflammation and used as an indicator of disease risk; however, the role of inflammation in disease is not completely understood. Methylation is an epigenetic modification in the DNA which plays a pivotal role in gene expression. In this study we evaluated differential DNA methylation patterns associated with blood CRP level to elucidate biological pathways and genetic regulatory mechanisms to improve the understanding of chronic inflammation. The racially and ethnically diverse participants in this study were included as 50% White, 41% Black or African American, 7% Hispanic or Latino/a, and 2% Native Hawaiian, Asian American, American Indian, or Alaska Native (total n = 13,433) individuals. We replicated 113 CpG sites from 87 unique loci, of which five were novel (CADM3, NALCN, NLRC5, ZNF792, and cg03282312), across a discovery set of 1,150 CpG sites associated with CRP level (p < 1.2E-7). The downstream pathways affected by DNA methylation included the identification of IFI16 and IRF7 CpG-gene transcript pairs which contributed to the innate immune response gene enrichment pathway along with NLRC5, NOD2, and AIM2. Gene enrichment analysis also identified the nuclear factor-kappaB transcription pathway. Using two-sample Mendelian randomization (MR) we inferred methylation at three CpG sites as causal for CRP levels using both White and Black or African American MR instrument variables. Overall, we identified novel CpG sites and gene transcripts that could be valuable in understanding the specific cellular processes and pathogenic mechanisms involved in inflammation.

ptx3a+ fibroblast/epicardial cells provide a transient macrophage niche to promote heart regeneration.

Macrophages conduct critical roles in heart repair, but the niche required to nurture and anchor them is poorly studied. Here, we investigated the macrophage niche in the regenerating heart. We analyzed cell-cell interactions through published single-cell RNA sequencing datasets and identified a strong interaction between fibroblast/epicardial (Fb/Epi) cells and macrophages. We further visualized the association of macrophages with Fb/Epi cells and the blockage of macrophage response without Fb/Epi cells in the regenerating zebrafish heart. Moreover, we found that ptx3a+ epicardial cells associate with reparative macrophages, and their depletion resulted in fewer reparative macrophages. Further, we identified csf1a expression in ptx3a+ cells and determined that pharmacological inhibition of the csf1a pathway or csf1a knockout blocked the reparative macrophage response. Moreover, we found that genetic overexpression of csf1a enhanced the reparative macrophage response with or without heart injury. Altogether, our studies illuminate a cardiac Fb/Epi niche, which mediates a beneficial macrophage response after heart injury.

Genetic variant rs1205 is associated with COVID-19 outcomes: The Strong Heart Study and Strong Heart Family Study.

BACKGROUND: Although COVID-19 infection has been associated with a number of clinical and environmental risk factors, host genetic variation has also been associated with the incidence and morbidity of infection. The CRP gene codes for a critical component of the innate immune system and CRP variants have been reported associated with infectious disease and vaccination outcomes. We investigated possible associations between COVID-19 outcome and a limited number of candidate gene variants including rs1205. METHODOLOGY/PRINCIPAL FINDINGS: The Strong Heart and Strong Heart Family studies have accumulated detailed genetic, cardiovascular risk and event data in geographically dispersed American Indian communities since 1988. Genotypic data and 91 COVID-19 adjudicated deaths or hospitalizations from 2/1/20 through 3/1/23 were identified among 3,780 participants in two subsets. Among 21 candidate variants including genes in the interferon response pathway, APOE, TMPRSS2, TLR3, the HLA complex and the ABO blood group, only rs1205, a 3' untranslated region variant in the CRP gene, showed nominally significant association in T-dominant model analyses (odds ratio 1.859, 95%CI 1.001-3.453, p = 0.049) after adjustment for age, sex, center, body mass index, and a history of cardiovascular disease. Within the younger subset, association with the rs1205 T-Dom genotype was stronger, both in the same adjusted logistic model and in the SOLAR analysis also adjusting for other genetic relatedness. CONCLUSION: A T-dominant genotype of rs1205 in the CRP gene is associated with COVID-19 death or hospitalization, even after adjustment for relevant clinical factors and potential participant relatedness. Additional study of other populations and genetic variants of this gene are warranted.

Pentraxin 3 exacerbates psoriasiform dermatitis through regulation of macrophage polarization.

OBJECTIVE: To elucidate the mechanism of Pentraxin 3 (PTX3) in the pathogenesis of psoriasiform dermatitis using Ptx3-knockout (Ptx3-KO) background mice. METHODS: An Imiquimod (IMQ)-induced murine psoriatic model was created using Ptx3-KO (Ptx3-/-) and wild-type (Ptx3+/+) mice. Skin lesion severity and expression of inflammatory mediators (IL-6 and TNFα) were assessed using PASI score and ELISA, respectively. Cutaneous tissues from the two mice groups were subjected to histological analyses, including HE staining, Masson staining, and Immunohistochemistry (IHC). The PTX3, iNOS, COX2, and Arg1 expressions were quantified and compared between the two groups. We used RNA-seq to clarify the underlying mechanisms of the disease. Flow cytometry was used to analyze systemic Th17 cell differentiation and macrophage polarization. RESULT: The psoriatic region exhibited a higher PTX3 expression than the normal cutaneous area. Moreover, PTX3 was upregulated in HaCaT cells post-TNFα stimulation. Upon IMQ stimulation, Ptx3-/- mice displayed a lower degree of the psoriasiform dermatitis phenotype compared to Ptx3+/+ mice. Consistent with the RNA-seq results, further experiments confirmed that compared to the wild-type group, the PTX3-KO group exhibited a generally lower IL-6, TNFα, iNOS, and COX2 expression and a contrasting trend in macrophage polarization. However, no significant difference in Th17 cell activation was observed between the two groups. CONCLUSIONS: This study revealed that PTX3 was upregulated in psoriatic skin tissues and TNFα-stimulated HaCaT cells. We also discovered that PTX3 deficiency in mice ameliorated the psoriasiform dermatitis phenotype upon IMQ stimulation. Mechanistically, PTX3 exacerbates psoriasiform dermatitis by regulating macrophage polarization rather than Th17 cell differentiation.

Unraveling the relationship between high-sensitivity C-reactive protein and frailty: evidence from longitudinal cohort study and genetic analysis.

BACKGROUND: This study aimed to investigate the association of high-sensitivity C-reactive protein (hs-CRP) with incident frailty as well as its effects on pre-frailty progression and regression among middle-aged and older adults. METHODS: Based on the frailty index (FI) calculated with 41 items, 6890 eligible participants without frailty at baseline from China Health and Retirement Longitudinal Study (CHARLS) were categorized into health, pre-frailty, and frailty groups. Logistic regression models were used to estimate the longitudinal association between baseline hs-CRP and incident frailty. Furthermore, a series of genetic approaches were conducted to confirm the causal relationship between CRP and frailty, including Linkage disequilibrium score regression (LDSC), pleiotropic analysis, and Mendelian randomization (MR). Finally, we evaluated the association of hs-CRP with pre-frailty progression and regression. RESULTS: The risk of developing frailty was 1.18 times (95% CI: 1.03-1.34) higher in participants with high levels of hs-CRP at baseline than low levels of hs-CRP participants during the 3-year follow-up. MR analysis suggested that genetically determined hs-CRP was potentially positively associated with the risk of frailty (OR: 1.06, 95% CI: 1.03-1.08). Among 5241 participants with pre-frailty at baseline, we found pre-frailty participants with high levels of hs-CRP exhibit increased odds of progression to frailty (OR: 1.39, 95% CI: 1.09-1.79) and decreased odds of regression to health (OR: 0.84, 95% CI: 0.72-0.98) when compared with participants with low levels of hs-CRP. CONCLUSIONS: Our results suggest that reducing systemic inflammation is significant for developing strategies for frailty prevention and pre-frailty reversion in the middle-aged and elderly population.

Inactivation of pentraxin 3 suppresses M2-like macrophage activity and immunosuppression in colon cancer.

BACKGROUND: The tumor microenvironment is characterized by inflammation-like and immunosuppression situations. Although cancer-associated fibroblasts (CAFs) are among the major stromal cell types in various solid cancers, including colon cancer, the interactions between CAFs and immune cells remains largely uncharacterized. Pentraxin 3 (PTX3) is responsive to proinflammatory cytokines and modulates immunity and tissue remodeling, but its involvement in tumor progression appears to be context-dependent and is unclear. METHODS: Open-access databases were utilized to examine the association of PTX3 expression and the fibroblast signature in colon cancer. Loss-of-function assays, including studies in tamoxifen-induced Ptx3 knockout mice and treatment with an anti-PTX3 neutralizing antibody (WHC-001), were conducted to assess the involvement of PTX3 in colon cancer progression as well as its immunosuppressive effect. Finally, bioinformatic analyses and in vitro assays were performed to reveal the downstream effectors and decipher the involvement of the CREB1/CEBPB axis in response to PTX3 and PTX3-induced promotion of M2 macrophage polarization. RESULTS: Clinically, higher PTX3 expression was positively correlated with fibroblasts and inflammatory response signatures and associated with a poor survival outcome in colon cancer patients. Blockade of PTX3 significantly reduced stromal cell-mediated tumor development. The decrease of the M2 macrophage population and an increase of the cytotoxic CD8+ T-cell population were observed following PTX3 inactivation in allografted colon tumors. We further revealed that activation of cyclic AMP-responsive element-binding protein 1 (CREB1) mediated the PTX3-induced promotion of M2 macrophage polarization. CONCLUSIONS: PTX3 contributes to stromal cell-mediated protumor immunity by increasing M2-like macrophage polarization, and inhibition of PTX3 with WHC-001 is a potential therapeutic strategy for colon cancer.

Mendelian randomization analysis identifies a genetic casual association between circulating C-reactive protein and intracerebral hemorrhage.

BACKGROUND: The causal effect of C-reactive protein (CRP) on intracerebral hemorrhage (ICH) remains controversial. We discussed the causal association of CRP with ICH based on two-sample Mendelian randomization. METHODS: The data from two genome-wide association studies (GWAS) of European ancestry was extracted, including circulating CRP levels (204,402 individuals) and ICH (1,687 cases and 201,146 controls). The inverse variance weighted (IVW) method was primary tool to evaluate the causal relationship of circulating CRP levels on ICH risk. MR-Egger regression and MR-PRESSO global test were utilized to identify pleiotropy. Heterogeneity was discussed with Cochran's Q test. The leave-one-out analysis explored the reliability of the results. RESULTS: 54 SNPs were identified as instrumental variables (IVs) for circulating CRP levels, and these IVs had no significant horizontal pleiotropy, heterogeneity, or bias. MR analysis demonstrated a causal relationship between elevated circulating CRP levels and decreased risk of ICH (ORIVW = 0.828, 95% CI 0.692-0.992, P = 0.040). CONCLUSION: Elevated circulating CRP levels demonstrated a significant potentially protective causal relationship with risk of ICH.

The death rate of COVID-19 infection in different SARS-CoV-2 variants was related to C-reactive protein gene polymorphisms.

The serum level of C-reactive protein (CRP) is a significant independent risk factor for Coronavirus disease 2019 (COVID-19). A link was found between serum CRP and genetic diversity within the CRP gene in earlier research. This study examined whether CRP rs1205 and rs1800947 polymorphisms were associated with COVID-19 mortality among various severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) variants. We genotyped CRP rs1205 and rs1800947 polymorphisms in 2023 deceased and 2307 recovered patients using the polymerase chain reaction-restriction fragment length polymorphism method. There was a significant difference between the recovered and the deceased patients in terms of the minor allele frequency of CRP rs1205 T and rs1800947 G. In all three variants, COVID-19 mortality rates were associated with CRP rs1800947 GG genotype. Furthermore, CRP rs1205 CC and rs1800947 GG genotypes showed higher CRP levels. It was found that the G-T haplotype was prevalent in all SARS-CoV-2 variants. The C-C and C-T haplotypes were statistically significant in Delta and Omicron BA.5 variants, respectively. In conclusion, polymorphisms within the CRP gene may relate to serum CRP levels and mortality among COVID-19 patients. In order to verify the utility of CRP polymorphism correlation in predicting COVID-19 mortality, a replication of these results is needed.

Recombinant expression and immune function analysis of C-reactive protein (CRP) from Hexagrammos otakii.

C-reactive protein (CRP) belongs to the short-chain pentraxin family and functions as a soluble pattern recognition molecule (PRM) aiding in host defense against pathogens. In the present study, a CRP gene, designated HoCRP, was cloned from Hexagrammos otakii for the first time. The full length of the HoCRP cDNA sequence is 821 bp, which contains an open reading frame (ORF) of 675 bp encoding a 224 amino acid protein. The deduced protein is predicted to have a theoretical isoelectric point (pI) of 5.30 and a molecular weight of 25.4 kDa. The recombinant HoCRP protein (rHoCRP) was expressed in E. coli to further characterize the functions of HoCRP. Saccharide binding experiments demonstrated that rHoCRP exhibited a high affinity for various pathogen-associated molecular patterns (PAMPs). Furthermore, bacterial binding and agglutination assays indicated that rHoCRP had the capability to recognize a wide spectrum of microorganisms. These findings suggest that HoCRP functions not only as a PRM for binding PAMPs but also as an immune effector molecule. Considering the role CRP plays in the classical complement pathway, the interaction between rHoCRP and rHoC1q was assessed and proven by a Pull-down and Elisa assay, which implied that rHoCRP may be able to activate complement. In addition, phagocytosis enhancement by rHoCRP in the presence or absence of complement components was analysed by flow cytometry. The results showed that rHoCRP could synergistically enhance the phagocytosis of RAW264.7 cells with complement, providing further evidence of complement activation by rHoCRP through the opsonization of specific complement components. In summary, our findings suggest that rHoCRP may play a crucial role in host antibacterial defense by recognizing pathogens, activating the complement system, and enhancing macrophage function.

Association of PTX3 gene polymorphisms and PTX3 plasma levels with leprosy susceptibility.

BACKGROUND: Pentraxin 3 (PTX3) is a soluble pattern recognition receptor that plays a crucial role in modulating the inflammatory response and activating the complement system. Additionally, plasma PTX3 has emerged as a potential biomarker for various infectious diseases. The aim of this study was to evaluate the association of PTX3 gene polymorphisms and PTX3 plasma levels with susceptibility to leprosy and clinical characteristics. METHODS: Patients with leprosy from a hyperendemic area in the Northeast Region of Brazil were included. Healthy household contacts and healthy blood donors from the same geographical area were recruited as a control group. The rs1840680 and rs2305619 polymorphisms of PTX3 were determined by real-time PCR. Plasma levels of PTX3 were determined by ELISA. RESULTS: A total of 512 individuals were included. Of these, 273 were patients diagnosed with leprosy; 53 were household contacts, and 186 were healthy blood donors. No association was observed between PTX3 polymorphisms and susceptibility to leprosy or development of leprosy reaction or physical disability. On the other hand, plasma levels of PTX3 were significantly higher in patients with leprosy when compared to household contacts (p = 0.003) or blood donors (p = 0.04). It was also observed that PTX3 levels drop significantly after multidrug therapy (p < 0.0001). CONCLUSIONS: Our results suggest that PTX3 may play an important role in the pathogenesis of leprosy and point to the potential use of this molecule as an infection marker.

Circulating microRNAs and hepcidin as predictors of iron homeostasis and anemia among school children: a biochemical and cross-sectional survey analysis.

BACKGROUND: MicroRNAs (miRNAs) can control several biological processes. Thus, the existence of these molecules plays a significant role in regulating human iron metabolism or homeostasis. PURPOSE: The study aimed to determine the role of circulating microRNAs and hepcidin in controlling iron homeostasis and evaluating possible anemia among school children. METHODS: The study was based on a biochemical and cross-sectional survey study that included three hundred fifty school children aged 12-18 years old. RT-PCR and immunoassay analysis were accomplished to estimate iron concentration, Hgb, serum ferritin (SF), soluble transferrin receptor (sTfR), total body iron stores (TIBs), total oxidative stress (TOS), total antioxidant capacity (TAC), α-1-acid glycoprotein (AGP), high sensitive C-reactive protein (hs-CRP), and miRNAs; miR-146a, miR-129b, and miR-122 in 350 school adolescents. RESULTS: Iron disorders were cross-sectionally predicted in 28.54% of the study population; they were classified into 14.26% with ID, 5.7% with IDA, and 8.6% with iron overload. The overall proportion of iron depletion was significantly higher in girls (20.0%) than in boys (8.6%). MicroRNAs; miR-146a, miR-125b, and miR-122 were significantly upregulated with lower hepcidin expression in adolescence with ID and IDA compared to iron-overloaded subjects, whereas downregulation of these miRNAs was linked with higher hepcidin. Also, a significant correlation was recorded between miRNAs, hepcidin levels, AGP, hs-CRP, TAC, and other iron-related indicators. CONCLUSION: Molecular microRNAs such as miR-146a, miR-125b, and miR-122 were shown to provide an additional means of controlling or regulating cellular iron uptake or metabolism either via the oxidative stress pathway or regulation of hepcidin expression via activating genes encoding Hfe and Hjv activators, which promote iron regulation. Thus, circulating miRNAs as molecular markers and serum hepcidin could provide an additional means of controlling or regulating cellular iron and be associated as valuable markers in diagnosing and treating cases with different iron deficiencies.

The effect of immunomodulatory drugs on aortic stenosis: a Mendelian randomisation analysis.

There are currently no approved pharmacological treatment options for aortic stenosis (AS), and there are limited identified drug targets for this chronic condition. It remains unclear whether inflammation plays a role in AS pathogenesis and whether immunomodulation could become a therapeutic target. We evaluated the potentially causal association between inflammation and AS by investigating the genetically proxied effects of tocilizumab (IL6 receptor, IL6R, inhibitor), canakinumab (IL1ß inhibitor) and colchicine (ß-tubulin inhibitor) through a Mendelian randomisation (MR) approach. Genetic proxies for these drugs were identified as single nucleotide polymorphisms (SNPs) in the gene, enhancer or promoter regions of IL6R, IL1ß or ß-tubulin gene isoforms, respectively, that were significantly associated with serum C-reactive protein (CRP) in a large European genome-wide association study (GWAS; 575,531 participants). These were paired with summary statistics from a large GWAS of AS in European patients (653,867 participants) to then perform primary inverse-variance weighted random effect and sensitivity MR analyses for each exposure. This analysis showed that genetically proxied tocilizumab was associated with reduced risk of AS (OR 0.56, 95% CI 0.45-0.70 per unit decrease in genetically predicted log-transformed CRP). Genetically proxied canakinumab was not associated with risk of AS (OR 0.80, 95% CI 0.51-1.26), and only one suitable SNP was identified to proxy the effect of colchicine (OR 34.37, 95% CI 1.99-592.89). The finding that genetically proxied tocilizumab was associated with reduced risk of AS is concordant with an inflammatory hypothesis of AS pathogenesis. Inhibition of IL6R may be a promising therapeutic target for AS management.

Branched-chain fatty acids affect the expression of fatty acid synthase and C-reactive protein genes in the hepatocyte cell line.

Fatty acids (FAs) are known to play an important role in human metabolism; however, still little is known about the functions of certain FA classes present in blood at relatively low concentrations. Examples of such compounds include branched-chain fatty acids (BCFAs). Recently, lowered BCFAs blood concentration was noticed in obese patients. An inverse correlation was found between serum concentrations of BCFAs and triglyceride levels, as well as C-reactive protein (CRP) concentration. Obesity is the most frequently observed component of metabolic syndrome and both disorders are accompanied by the dysregulation of FAs metabolism. However, not all of them are well understood. Our study is the first attempt at presenting the opposite effects of an iso-BCFA (14-methylpentadecanoic acid, 14-MPA) and an anteiso-BCFA (12-methyltetradecanoic acid, 12-MTA) on selected genes related to fatty acid synthesis and inflammation: FASN, SREBP1, CRP, and IL-6 in the HepG2 cell line. We observed lowered expression of FASN, SREBP1, CRP, and IL-6 in cells treated with 14-MPA in comparison with control cells. In contrast, supplementation with 12-MTA caused opposite effects: increased mRNA levels of FASN, CRP, and IL-6. 12-MTA did not influence SREBP1 expression. The results of our preliminary study may suggest potential benefits of the supplementation of iso-BCFAs in obese patients, for inflammation and hypertriglyceridemia prevention.

Mutations on a conserved distal enhancer in the porcine C-reactive protein gene impair its expression in liver.

C-reactive protein (CRP) is an evolutionary highly conserved protein. Like humans, CRP acts as a major acute phase protein in pigs. While CRP regulatory mechanisms have been extensively studied in humans, little is known about the molecular mechanisms that control pig CRP gene expression. The main goal of the present work was to study the regulatory mechanisms and identify functional genetic variants regulating CRP gene expression and CRP blood levels in pigs. The characterization of the porcine CRP proximal promoter region revealed a high level of conservation with both cow and human promoters, sharing binding sites for transcription factors required for CRP expression. Through genome-wide association studies and fine mapping, the most associated variants with both mRNA and protein CRP levels were localized in a genomic region 39.3 kb upstream of CRP. Further study of the region revealed a highly conserved putative enhancer that contains binding sites for several transcriptional regulators such as STAT3, NF-kB or C/EBP-ß. Luciferase reporter assays showed the necessity of this enhancer-promoter interaction for the acute phase induction of CRP expression in liver, where differences in the enhancer sequences significantly modified CRP activity. The associated polymorphisms disrupted the putative binding sites for HNF4α and FOXA2 transcription factors. The high correlation between HNF4α and CRP expression levels suggest the participation of HNF4α in the regulatory mechanism of porcine CRP expression through the modification of its binding site in liver. Our findings determine, for the first time, the relevance of a distal regulatory element essential for the acute phase induction of porcine CRP in liver and identify functional polymorphisms that can be included in pig breeding programs to improve immunocompetence.

TNF-α versus IL-6 Genes Expression levels in Active Rheumatoid Arthritis: Clinical and Laboratory Determinants.

This study intended to compare the expression levels of tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) genes in active rheumatoid arthritis (RA) patients who were receiving conventional synthetic disease-modifying drugs (csDMARDs) and to find the clinical and laboratory determinants affecting TNF-α and IL-6 genes expression levels among active RA patients. This was a cross sectional study that included 108 active RA patients who were receiving csDMARDs. A detailed history was reviewed for all patients in addition to a complete physical examination and assessment of the 28-joint disease activity score (DAS28). Some laboratory measures were recorded as C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and serum rheumatoid factor (RF). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure expression levels of TNF- α and IL-6 genes. In active RA patients, TNF-α and IL-6 genes expression levels were significantly correlated to each other (p<0.001, r=0.788). Also, both had positive correlations with the age and DAS28 among RA patients (p<0.001). IL-6 and TNF-α expression levels were significantly higher in RA patients with high DAS28 scores (p<0.001). Most RA patients (81.5%) had relatively higher IL-6 gene expression levels than TNF-α. RA patients with relatively high IL-6 expression levels were younger in age and had shorter disease duration and less DAS28 than RA patients with relatively high TNF-α gene expression levels. In addition, they had higher CRP and RF levels. Young age was detected as a significant predictor for relatively higher IL-6 gene expression levels than TNF-α. In conclusion, most active RA patients had higher IL-6 gene expression levels than TNF-α. Young age could be considered a significant predictor for relatively high IL-6 gene expression levels among active RA patients.