An evaluation of association between common variants in C4BPB/C4BPA genes and schizophrenia

Effects of olanzapine on anhedonia in schizophrenia: mediated by complement factor H

Background

Anhedonia is a trans-diagnostic symptom in schizophrenia and MDD. Our recent work indicated that increased plasma level of complement factor H (CFH) is associated with anhedonia in major depressive disorder. This study hypothesized that CFH is likely to be a biomarker of anhedonia in schizophrenia.

Methods

A 12-week prospective study is performed to observe the effects of olanzapine on anhedonia and CFH. We used the Chinese version of Snaith-Hamilton Pleasure Scale (SHAPS) to evaluate anhedonic phenotype in patients with schizophrenia. Plasma levels of C-reactive protein (CRP), C3, C4 and CFH were measured.

Results

Of the recruited 152 samples, patients with anhedonia were found in 99/152 (65.13%). Patients with anhedonia had notably higher PANSS negative subscores, SHAPS total score and higher level of plasma CFH than those without anhedonia (Ps<0.05). Stepwise multivariate linear regression analysis showed that increasing level of plasma CFH was a risk factor for SHAPS total score (β = 0.18, p = 0.03). Of the 99 patients with anhedonia, 74 completed the 12-week follow-up. We observed significantly reduced scores of PANSS, SHAPS and decreased plasma CFH level, when the patients completed this study. The change of SHAPS total score is positively correlated with the level of CFH decrease (p = 0.02).

Conclusion

Our results implied that plasma CFH levels may be a biomarker for anhedonia in schizophrenia, and the effect of olanzapine on treating anhedonia is through decreasing plasma CFH levels.

Classical complement pathway factor alterations in narcolepsy

OBJECTIVE

Narcolepsy is a chronic sleep disorder long hypothesised to be an autoimmune disease. Complement-mediated immune mechanisms have not been investigated in detail in narcolepsy. Our aim was to establish the significance of classical pathway activation in narcolepsy.

METHODS

Sera of 42 narcolepsy patients and 26 healthy controls were screened with ELISA to determine the levels of C1q, C3a, C4d and complement component 4 binding protein (C4BP). A home-made ELISA method was developed to detect antibodies to C4BP-alpha (anti-C4BPA). The correlation between complement levels and clinical findings was examined.

RESULTS

C1q levels were significantly higher in narcolepsy patients while C4d and C4BP levels were significantly lower compared to healthy controls. C3a levels were comparable among patients and controls. Eleven narcolepsy patients showed serum anti-C4BPA levels. Total rapid eye movements (REM) time, sleep onset latency, REM sleep latency, sleep activity, percentage of wakefulness after sleep onset and Epworth sleepiness scale scores were correlated with levels of different complement factors.

CONCLUSION

Complement-mediated immune mechanisms might partake in narcolepsy pathogenesis. The precise role of autoantibodies on complement level alterations needs to be investigated. Levels of complement factors and degradation products may potentially be utilised as biomarkers to predict the clinical severity of narcolepsy.

NLRP3 Influences Cognitive Function in Schizophrenia in Han Chinese

It has been proposed that immune abnormalities may be implicated with pathophysiology of schizophrenia. The nod-like receptor pyrin domain-contraining protein 3 (NLRP3) can trigger immune-inflammatory cascade reactions. In this study, we intended to identify the role of gene encoding NLRP3 (NLRP3) in susceptibility to schizophrenia and its clinical features. For the NLRP3 mRNA expression analysis, 53 drug-naïve patients with first-episode schizophrenia and 56 healthy controls were enrolled. For the genetic study, a total of 823 schizophrenia patients and 859 controls were recruited. Among them, 239 drug-naïve patients with first-episode schizophrenia were enrolled for clinical evaluation. There is no significant difference in NLRP3 mRNA levels between patients with schizophrenia and healthy controls (p = 0.07). We did not observe any significant differences in allele and genotype frequencies of rs10754558 polymorphism between the schizophrenia and control groups. We noticed significant differences in the scores of RBANS attention and total scores between the patients with different genotypes of rs10754558 polymorphism (p = 0.001 and p < 0.01, respectively). Further eQTL analysis presented a significant association between the rs10754558 polymorphism and NLRP3 in frontal cortex (p = 0.0028, p = 0.028 after Bonferroni correction). Although our findings did not support NLRP3 confer susceptibility to schizophrenia, NLRP3 may be a risk factor for cognitive impairment, especially attention deficit in this disorder.

Genome-wide gene expression changes in postpartum depression point towards an altered immune landscape

Maternal postpartum depression (PPD) is a significant public health concern due to the severe negative impact on maternal and child health and well-being. In this study, we aimed to identify genes associated with PPD. To do this, we investigated genome-wide gene expression profiles of pregnant women during their third trimester of pregnancy and tested the association of gene expression with perinatal depressive symptoms. A total of 137 women from a cohort from the University of North Carolina, USA were assessed. The main phenotypes analysed were Edinburgh Postnatal Depression Scale (EPDS) scores at 2 months postpartum and PPD (binary yes/no) based on an EPDS cutoff of 10. Illumina NextSeq500/550 transcriptomic sequencing from whole blood was analysed using the edgeR package. We identified 71 genes significantly associated with postpartum depression scores at 2 months, after correction for multiple testing at 5% FDR. These included several interesting candidates including TNFRSF17, previously reported to be significantly upregulated in women with PPD and MMP8, a matrix metalloproteinase gene, associated with depression in a genome-wide association study. Functional annotation of differentially expressed genes revealed an enrichment of immune response-related biological processes. Additional analysis of genes associated with changes in depressive symptoms from recruitment to 2 months postpartum identified 66 genes significant at an FDR of 5%. Of these genes, 33 genes were also associated with depressive symptoms at 2 months postpartum. Comparing the results with previous studies, we observed that 15.4% of genes associated with PPD in this study overlapped with 700 core maternal genes that showed significant gene expression changes across multiple brain regions (P = 7.9e-05) and 29-53% of the genes were also associated with estradiol changes in a pharmacological model of depression (P values range = 1.2e-4-2.1e-14). In conclusion, we identified novel genes and validated genes previously associated with oestrogen sensitivity in PPD. These results point towards the role of an altered immune transcriptomic landscape as a vulnerability factor for PPD.

Sperm quality and oxidative stress in chub Squalius orientalis and Padanian barbel Barbus plebejus (Teleostei: Cyprinidae) after in vitro exposure to low doses of bisphenol A

In an aquatic environment, the presence of Bisphenol A (BPA) adversely affects reproduction, biology, behavior, gonads, and early larval development of fish due to being endocrine-disrupting compound. In addition, the detected concentration of BPA in water bodies is reported to be higher than 0.41 μg/L. As an alternative tool, sperm cells are used in toxicological assays for the reliable and practical assessment. For these reasons, we examined the effects of in vitro exposure of BPA on sperm quality of chub Squalius oriantalis and Padanian barbel Barbus plebejus. Spermatozoa were exposed to lower concentrations (0, 0.5, 1.25, 2.5, and 5 µg/L) of BPA for 2 h. The enzymatic activities [glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD)] and lipid peroxidation (MDA) were evaluated in spermatozoa. The results demonstrated that BPA exposure significantly decreased activities of SOD and GSH-Px but increased CAT activity and lipid peroxidation (MDA). Compared to control, the percentage and duration of sperm motility significantly decreased. Overall, spermatozoa clearly showed the sensitivity to lower concentrations of BPA.

Effects of perinatal exposure to BPA, BPF and BPAF on liver function in male mouse offspring involving in oxidative damage and metabolic disorder

Bisphenols (BPs) are common environmental pollutants that are ubiquitous in the natural environment and can affect human health. In this study, we explored the effects of perinatal exposure to BPA, BPF and BPAF on liver function involving in oxidative damage and metabolic disorders in male mouse offspring. We found that BPA exposure impairs the antioxidant defense system, increases lipid peroxidation, and causes oxidative damage in the liver. Furthermore, the levels of 13 metabolites were significantly altered following BPA exposure. We found that BPF exposure significantly increased the expression and activity of CAT, suggesting disturbances in the antioxidant defense system. Moreover, BPF exposure led to metabolic disorders in the liver due to changes in the levels of 8 key metabolites. Exposure to BPAF caused no negative effects on oxidative damage, but altered the levels of β-glucose and glycogen. In summary, perinatal exposure to BPA, BPF and BPAF differentially influence oxidative damage and metabolic disorders in the livers of male mouse offspring. The impact of early life exposure to BPs now warrants future investigations.

Genome-wide differential mRNA expression profiles in follicles of two breeds and at two stages of estrus cycle of gilts

Estrus expression by gilts and sows is hereditable and important for heat detection. To better understand the molecular biological mechanisms of estrus expression in gilts, the mRNA expression profiles of follicular tissue from Large White gilts in diestrus (LD, n = 3) and estrus (LE, n = 3), and Chinese indigenous Mi gilts in diestrus (MD, n = 2) and estrus (ME, n = 3) were investigated using RNA sequencing. We detected 122,804-335,295 SNPs, 6,140-14,947 InDel and 12 types of AS events (39.57% TSS, 34.90% TTS) in 11 samples. A total of 2,838 differentially expressed genes (DEGs) were found in LD vs MD, LE vs ME, LE vs LD, or ME vs MD comparisons. Two DEGs (ACP5 and PIGS) were observed in all comparisons. Two new genes (ENSSSCG00000028235 and ENSSSCG00000021903) were exclusively expressed in Mi and Large White gilts, respectively. Bioinformatics analyses indicate that these DEGs are involved in single-organism process, catalytic activity, cell adhesion and enriched in ECM-receptor interaction, olfactory transduction, ovarian steroidogenesis, steroid biosynthesis and CAMs signaling pathways. These results of RNA-Seq have provided important information for screening the key functional genes or molecular markers of estrus expression in gilts.

Association of single nucleotide polymorphisms in the 5' upstream region of the C4BPA gene with essential hypertension in a northeastern Han Chinese population

A previous study of the authors using microarray analysis indicated that the expression of complement component 4 binding protein (C4BP)A is upregulated in essential hypertension (EH) patients, but the association between C4BPA variations and EH has not yet been clearly demonstrated. Since the 5′ upstream region is known to serve important roles in the gene expression regulation, the present study aimed to identify and analyze the association of single nucleotide polymorphisms (SNPs) in the 5′ upstream region between the C4BPA gene with EH in a case-control study among a northeastern Han Chinese population through direct sequencing as well as genotype detection. A total of 822 unrelated participants were included. The higher expression level of C4BPA in the peripheral blood of patients with EH was verified through reverse transcription-quantitative polymerase chain reaction and ELISA. A total of four SNPs, rs73079108, rs74148971, rs77660718 and rs11120211 were identified in the 5′ upstream region of C4BPA. Association analysis demonstrated that the genotypic frequencies of rs73079108 were significantly different between EH and the control groups (P=0.011), and A allelic frequency was lower in EH (P<0.001). Logistic regression analysis indicated that the rs73079108 polymorphism was closely associated with EH (AA:GA:GG genetic model: P=0.007, odds ratio (OR)=0.604, 95% confidence interval (CI) [0.418–0.873]; AA+GA:GG genetic model: P=0.005, OR=0.806, 95% CI[0.382–0.841]), and the A allele may be a protective factor. Subgroup analysis by sex and BMI presented concordant conclusions in female and non-obese samples. Further analysis indicated that rs73079108 was associated with systolic blood pressure (P<0.001), diastolic blood pressure (P=0.001) and fast blood glucose (FBG) (P=0.021). In addition, rs73079108 GA and GG carriers reported a significant increase in the level of the protein encoded by C4BPA than those of AA carriers. The rs73079108 polymorphism in the 5′ upstream region of C4BPA was associated with EH, and rs73079108-A may be an independent predictor.

A Preliminary Genetic Analysis of Complement 3 Gene and Schizophrenia

Complement pathway activation was found to occur frequently in schizophrenia, and complement 3 (C3) plays a major role in this process. Previous studies have provided evidence for the possible role of C3 in the development of schizophrenia. In this study, we hypothesized that the gene encoding C3 (C3) may confer susceptibility to schizophrenia in Han Chinese. We analyzed 7 common single nucleotide polymorphisms (SNPs) of C3 in 647 schizophrenia patients and 687 healthy controls. Peripheral C3 mRNA expression level was measured in 23 drug-naïve patients with schizophrenia and 24 controls. Two SNPs (rs1047286 and rs2250656) that deviated from Hardy-Weinberg equilibrium were excluded for further analysis. Among the remaining 5 SNPs, there was no significant difference in allele and genotype frequencies between the patient and control groups. Logistic regression analysis showed no significant SNP-gender interaction in either dominant model or recessive model. There was no significant difference in the level of peripheral C3 expression between the drug-naïve schizophrenia patients and healthy controls. In conclusion, the results of this study do not support C3 as a major genetic susceptibility factor in schizophrenia. Other factors in AP may have critical roles in schizophrenia and be worthy of further investigation.