Metal concentrations in cerebrospinal fluid,blood, serum,plasma, hair,and nails in amyotrophic lateral sclerosis: A systematic review and meta-analysis

BackgroundAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with progressive muscle wasting, paralysis, and respiratory failure. Whereas approximately 10–15 % of ALS cases are familial, the etiology of the remaining, sporadic ALS cases remains largely unknown. Environmental exposures have been suggested as causative factors for decades, and previous studies have found elevated concentrations of metals in ALS patients.PurposeThis meta-analysis aims to assess metal concentrations in body fluids and tissues of ALS patients.MethodsWe searched the MEDLINE and EMBASE databases on December 7th, 2022 for cross-sectional, case-control, and cohort studies which measure metal concentrations in whole blood, blood plasma, blood serum, cerebrospinal fluid (CSF), urine, erythrocytes, nail, and hair samples of ALS patients. Meta-analysis was then performed when three or more articles existed for a comparison.FindingsTwenty-nine studies measuring 23 metals were included and 13 meta-analyses were performed from 4234 screened entries. The meta-analysis results showed elevated concentrations of lead and selenium. Lead, measured in whole blood in 6 studies, was significantly elevated by 2.88 µg/L (95 % CI: 0.83–4.93, p = 0.006) and lead, measured in CSF in 4 studies, was significantly elevated by 0.21 µg/L (95 % CI: 0.01 – 0.41, p = 0.04) in ALS patients when compared to controls. Selenium, measured in serum/plasma in 4 studies, was significantly elevated by 4.26 µg/L (95% CI: 0.73 – 7.79, p = 0.02) when compared to controls.Analyses of other metal concentrations showed no statistically significant difference between the groups.ConclusionLead has been discussed as a possible causative agent in ALS since 1850. Lead has been found in the spinal cord of ALS patients, and occupational exposure to lead is more common in ALS patients than in controls. Selenium in the form of neurotoxic selenite has been shown to geochemically correlate to ALS occurrence in Italy. Although no causal relationship can be established from the results of this meta-analysis, the findings suggest an involvement of lead and selenium in the pathophysiology of ALS. After a thorough meta-analysis of published studies on metal concentrations in ALS it can only be concluded that lead and selenium are elevated in ALS.     

Serum copper and zinc levels in breast cancer: A meta-analysis

BackgroundMore and more studies have investigated the relationship between serum copper (Cu) and/or zinc (Zn) levels and breast cancer (BC). However, the results are inconsistent. It is unclear whether the serum Cu to Zn ratio (Cu/Zn) is associated with BC risk. Therefore, we evaluated serum Cu and Zn concentrations, and Cu/Zn in BC through meta-analysis.Materials and methodsStudies reporting serum Cu and/or Zn concentrations in BC patients and controls from 1991 to 2020 were identified from PubMed, CNKI, and Wanfang databases online. Based on a random effects model, summary standard mean differences (SMDs) and the corresponding 95 % confidence intervals (95 % CIs) were applied to compare the serum levels of Cu, Zn and Cu/Zn between BC patients and controls.ResultsThirty-six eligible studies involving 5747 female subjects were included. The present study illustrated that the BC patients had significantly higher serum Cu levels than healthy controls (HC) (SMD (95 % CI): 1.99(1.48, 2.49)) and patients with benign breast diseases (BD) (SMD (95 % CI): 0.99(0.38, 1.61)). However, Zn concentrations were statistically decreased in BC patients than HC (SMD (95 % CI): -1.20(-1.74, -0.66)) and BD (SMD (95 % CI): -1.13 (-1.73, -0.54)). Cu/Zn concentrations were remarkably increased in BC patients than HC (SMD (95 % CI): 2.75(1.79, 3.60)) and BD (SMD (95 % CI): 2.98(1.91, 4.05)) in some studies.ConclusionThe results show that elevated serum levels of Cu and Cu/Zn, as well as decreased Zn might be associated with increased risk of breast cancer. These three parameters have the potential to distinguish breast cancer from benign breast diseases.     

Growth differentiation factor 15 is a promising diagnostic and prognostic biomarker in colorectal cancer

Although various studies have demonstrated that growth differentiation factor 15 (GDF15) might be a potential diagnostic and prognostic marker in colorectal cancer (CRC) patients, the results are inconsistent and the statistical power of individual studies is also insufficient. An original study was conducted to explore the diagnostic and prognostic value of serum GDF15 in CRC patients. We also conducted a meta‐analysis study which aimed to summarize the diagnostic and prognostic performance of serum GDF15 in CRC. We searched PubMed and ISI Web of Knowledge up to 1 November 2014 for eligible studies. In order to explore the diagnostic performance of GDF15, standardized mean difference (SMD) and their 95% confidence intervals (CI) were estimated and receiver‐operating characteristic (ROC) curves were constructed. For prognostic meta‐analysis, study‐specific hazard ratios (HRs) of serum GDF15 for survival were summarized. A total of eight studies were included in the meta‐analyses. Our results revealed that serum GDF15 levels in CRC patients were higher than those in healthy controls (SMD = 1.08, 95% CI: 0.56–1.59, P < 0.001). For discriminating CRC from healthy controls, the AUC of GDF15 was 0.816 (95% CI: 0.792–0.838). The sensitivity and specificity were 58.9% (95% CI: 55.0–62.8) and 92.08% (95% CI: 89.2–94.4), respectively, when a cut‐off value of 1099 pg/ml was established. Besides, higher GDF15 expression level was associated with worse overall survival for CRC patients (pooled HR = 2.09, 95% CI: 1.47–2.96). In conclusion, the present meta‐analysis suggests that serum GDF15 may be a useful diagnostic and prognostic biomarker for CRC.     

Serum Selenium Levels and Cervical Cancer: Systematic Review and Meta-Analysis

Several studies have investigated the relationship between serum Se concentration and cervical cancer, but the results were inconsistent. Thus, we conducted a systematic review and meta-analysis to evaluate the association between serum selenium levels and cervical cancer. Twelve studies investigating the association by univariate analysis and five studies by multivariate analysis were identified after a systematic search of PubMed, Wanfang, CNKI, and SinoMed databases. Standard mean differences (SMD) or odds ratios (OR) with the corresponding 95% confidence intervals (CI) were pooled to compare the selenium levels between different groups. In univariate analysis, serum selenium levels in cervical cancer cases were significantly lower than in controls (SMD = ?4.86, 95% CI ?6.03–3.69). Subgroup analysis showed consistent results. In multivariate analysis, serum selenium levels in cervical cancer cases were also significantly lower than in controls (OR = 0.55, 95% CI 0.42–0.73). After treatment, the serum selenium levels increased significantly (SMD = 2.59, 95% CI 0.50–4.69). In conclusion, high serum selenium levels were associated with cervical cancer, and selenium exposure might be a protective factor for cervical cancer.     

Serum and Hair Nickel Levels and Breast Cancer: Systematic Review and Meta-Analysis

Several studies have investigated the relationship between serum and hair nickel (Ni) concentration and breast cancer, but the results were inconsistent. Thus, we conducted a systematic review and meta-analysis to evaluate the association between serum and hair nickel levels and breast cancer. Nine studies determining the serum nickel levels and six studies evaluating the hair nickel levels were identified in a systematic search of PubMed, China Knowledge Resource Integrated Database, Wanfang, and China Biomedical Literature Service System databases. Based on a random-effects model, standard mean differences (SMD) and the corresponding 95% confidence intervals (CI) were pooled to compare the nickel levels between different groups. Compared with healthy controls, the serum nickel levels in breast cancer were significantly higher (SMD (95% CI) 1.76 (0.82, 2.70)), as well as in those post-treated cases (SMD (95% CI) 2.56 (1.18, 3.94)). For breast cancer cases, the treatment made no significant decrease in serum nickel levels (SMD (95% CI) ?0.29 (?1.17, 0.59)). In hair, the nickel levels in breast cancer were slightly higher than in controls, but not significant (SMD (95% CI) 0.16 (?1.08, 1.40)). In conclusion, high serum nickel levels were associated with breast cancer, and nickel exposure might be a risk factor for breast cancer.     

Association Between Tumor Necrosis Factor-α and Diabetic Peripheral Neuropathy in Patients with Type 2 Diabetes: a Meta-Analysis

Tumor necrosis factor-α (TNF-α) is a cell signaling protein involved in systemic inflammation, and is also an important cytokine in the acute phase reaction. Several studies suggested a possible association between TNF-α and diabetic peripheral neuropathy (DPN) in type 2 diabetic patients, but no accurate conclusion was available. A systematic review and meta-analysis of observational studies was performed to comprehensively assess the association between serum TNF-α levels and DPN in type 2 diabetic patients. We searched Pubmed, Web of Science, Embase, and China Biology Medicine (CMB) databases for eligible studies. Study-specific data were combined using meta-analysis. Fourteen studies were finally included into the meta-analysis, which involved a total of 2650 participants. Meta-analysis showed that there were obviously increased serum TNF-α levels in DPN patients compared with type 2 diabetic patients without DPN (standard mean difference [SMD]?=?1.203, 95 % CI 0.795–1.611, P?<?0.001). There were also obviously increased levels of serum TNF-α in diabetic patients with DPN when compared with healthy controls (SMD?=?2.364, 95 % CI 1.333–3.394, P?<?0.001). In addition, there were increased serum TNF-α levels in painful DPN patients compared with painless DPN patients (SMD?=?0.964, 95 % CI 0.237–1.690, P?=?0.009). High level of serum TNF-α was significantly associated with increased risk of DPN in patients with type 2 diabetes (odds ratio [OR]?=?2.594, 95 % CI 1.182–5.500, P?=?0.017). Increased serum levels of TNF-α was not associated with increased risk of painful DPN in patients with type 2 diabetes (OR?=?2.486, 95 % CI 0.672–9.193, P?=?0.172). Sensitivity analysis showed that there was no obvious change in the pooled estimates when omitting single study by turns. Type 2 diabetic patients with peripheral neuropathy have obviously increased serum TNF-α levels than type 2 diabetic patients without peripheral neuropathy and healthy controls, and high level of serum TNF-α may be associated with increased risk of peripheral neuropathy independently. Further prospective cohort studies are needed to assess the association between TNF-α and DPN.     

Low Serum Levels of Zinc,Copper, and Iron as Risk Factors for Osteoporosis: a Meta-analysis

Zinc (Zn), copper (Cu), and iron (Fe) are essential trace elements for the growth, development, and maintenance of healthy bones. However, there are conflicting reports as to the relationship between serum level of Zn, Cu, or Fe and osteoporosis (OP). The purpose of the present study is to clarify the relationship between serum Zn, Cu, or Fe and OP using a meta-analysis approach. We searched all articles indexed in PubMed published up to May 2014 concerning the association between serum level of Zn, Cu, or Fe and OP. Eight eligible articles involving 2,188 subjects were identified. Overall, pooled analysis indicated that patients with OP had a lower serum level of Zn, Cu, or Fe than the healthy controls (Zn standardized mean difference (SMD)?=??1.396, 95 % confidence interval (CI)?=?[?2.129, ?0.663]; Cu SMD?=??0.386, 95 % CI?=?[?0.538, ?0.234]; Fe SMD?=??0.22, 95 % CI?=?[?0.30, ?0.13]). Further subgroup analysis found that geographical location and gender had an influence on the serum level of Zn in OP and healthy controls, but not on the serum level of Cu or Fe. No evidence of publication bias was observed. In conclusion, this meta-analysis suggests that low serum levels of Zn, Cu, and Fe seem to be important risk factors for OP and well-designed studies with adequate control for confounding factors are required in future investigations.     

YKL-40 in patients with end-stage renal disease receiving haemodialysis

Purpose: This study aimed to determine serum YKL-40 in patients with end-stage renal disease (ESRD) on haemodialysis (HD) and to evaluate the prognostic value of serum YKL-40.

Methods: Patients >18?years on maintenance HD were included. Serum YKL-40 was measured using ELISA before and after a single HD treatment.

Results: A total of 306 patients were included. Median serum YKL-40 concentration was 238?µgL^?1 (IQR: 193–291?µgL^?1) before HD treatment and 198?µgL^?1 (IQR: 147–258?µgL^?1) after HD treatment, which corresponded to age-corrected 93th percentile in healthy subjects. All-cause mortality after 2.8?years was 35.9%. Patients with serum YKL-40 in the highest quartile compared with the lowest quartile had a univariate HR of 4.0 (95% CI: 2.2–7.3, p?p?=?0.01) in multivariate analysis. Time-dependent receiver operating characteristic curves showed that serum YKL-40 after HD treatment had significant higher area under the curves from 90?d (p?=?0.004) and throughout the rest of the follow-up period when compared to serum YKL-40 before HD treatment.

Conclusion: YKL-40 was highly elevated in patients with ESRD on HD, and dialysis reduced serum YKL-40 concentrations approximately one-sixth. YKL-40 measured after dialysis was independently associated with mortality in HD patients.     

Association Between Serum Level of Magnesium and Postmenopausal Osteoporosis: A Meta-analysis

There are conflicting reports as to the association between serum level of magnesium (Mg) and postmenopausal osteoporosis (OP). The purpose of the present study is to clarify the association between serum level of Mg and postmenopausal OP using a meta-analysis approach. We searched articles indexed in Pubmed and the Chinese Journal Full-text Database (CJFD) published as of October 2013 that met our predefined criteria. Seven eligible studies involving 1,349 postmenopausal women from 12 case-control study arms were identified. Overall, pooled analysis indicated that postmenopausal osteoporotic women had a lower serum level of Mg than the healthy controls (standardized mean difference [SMD]?=??0.55, 95 % confidence interval [CI]?=??0.83 to ?0.26). Further subgroup analysis found a similar pattern in Turkey (SMD?=??0.66, 95 % CI?=??0.99 to ?0.32) and Belgium (SMD?=??0.98, 95 % CI?=??1.91 to ?0.05), but not in China (SMD?=?0.02, 95 % CI?=??0.21 to 0.26). And the difference of serum level of Mg between postmenopausal osteoporotic women and healthy controls below the age of 60 years (SMD?=??0.61, 95 % CI?=??1.09 to ?0.13) was similar to that among the population over 60 years (SMD?=??0.49, 95 % CI?=??0.80 to ?0.18).In conclusion, this meta-analysis suggests that the low serum level of Mg seems to be a risk factor for OP among the postmenopausal women. However, the subgroup analysis found that there was contradiction regarding races and geography, like China and Turkey. Thus, this finding needs further confirmation by trans-regional multicenter study to obtain better understanding of causal relationships between serum Mg and postmenopausal OP.     

Zinc and Copper Levels in Bladder Cancer: A Systematic Review and Meta-Analysis

It is well documented that oxidative stress is involved in the pathogenesis of bladder cancer. Zinc (Zn) and copper (Cu) are important components of antioxidants. However, the association between Zn or Cu levels and bladder cancer remains elusive. The present study was designed to investigate the alteration of serum and urinary levels of Zn or Cu in bladder cancer patients compared with controls by performing a systematic review. We searched the PubMed, Embase, and Cochrane databases from January 1990 to March 2013 to identify studies that met our predefined criteria. Six studies were included. Bladder cancer patients demonstrated significantly lower levels of serum Zn (three studies, random effects standard mean deviation (SMD): ?1.072, 95 % CI: ?1.489 to ?0.656, P <0.0001), markedly higher levels of serum Cu (three studies, random effects SMD: 1.069, 95 % CI: 0.302 to 1.836, P?=?0.006) and urinary Zn (three studies, random effects SMD: 2.114, 95 % CI: 0.328 to 3.899, P?=?0.02) compared with controls. No obvious difference was observed in urinary Cu levels between bladder cancer patients and controls (two studies, random effects SMD: 0.153, 95 % CI: ?0.244 to 0.55, P?=?0.449). No evidence of publication bias was observed. In conclusion, the disorder of Zn and Cu is closely associated with bladder cancer. Frequent monitoring and early intervention should be recommended.     

Serum levels of glial fibrillary acidic protein and Nogo-A in children with autism spectrum disorders

Context: Improved biomarkers would facilitate the diagnosis and treatment of autism spectrum disorders (ASD).

Objective: Our objective was to examine the levels of Nogo-A and glial fibrillary acidic protein (GFAP) in children with ASD.

Materials and methods: Serum concentrations of GFAP and Nogo-A were determined by enzyme-linked immunosorbent assay.

Results: In this preliminary study, we found that serum Nogo-A was not found significantly different between groups, while serum levels of GFAP were significantly lower in ASD than controls.

Discussion and conclusions: It will be of great interest to determine other potential causes of elevated serum levels of GFAP, and whether this elevation has any phenotypic effect.     

Association Between Serum Zinc Levels and the Risk of Parkinson’s Disease: a Meta-Analysis

Recent studies have found that the serum zinc levels were associated with the risk of Parkinson’s disease (PD), but the results were inconsistent. Thus, we conducted a meta-analysis to summarize the evidence from observational studies between them. Pertinent studies were identified by a search in PubMed, Embase, and Web of science up to July, 10, 2016. Standardized mean difference (SMD) and 95% confidence intervals (CI) with random-effect model was used to combine the results. Subgroup analysis and meta-regression were also conducted. Publication bias was estimated using Begg’s regression asymmetry test. A total of 11 articles involving 822 PD patients and 777 healthy controls were included in the meta-analysis. Our meta-analysis results revealed that the serum zinc levels in PD patients were significantly lower than those in health controls (SMD = ?0.779, 95%CI = [?1.323, ?0.234], P < 0.001). The association was also significant oriental studies (SMD = ?1.601, 95%CI = [?2.398, ?0.805], P < 0.001). No publication bias was found. The current study indicated that serum zinc levels in PD patients were significantly lower than those in healthy controls.     

Effects of sodium glucose cotransporter-2 inhibitors on serum uric acid in type 2 diabetes mellitus: A systematic review with an indirect comparison meta-analysis

To describe the effects of sodium-glucose co-transporter 2 (SGLT2) inhibitors on serum uric acid (SUA) in patients with type 2 diabetes mellitus (T2DM). PubMed, EMBASE, and CENTRAL were searched for randomized controlled trials of SGLT2 inhibitors in patients with T2DM up to Aug 10, 2017, without language or date restrictions. Thirty-one studies totaling 13,650 patients were included. SGLT2 inhibitors significantly decreased SUA levels compared with placebo, canagliflozin WMD –37.02?μmol/L, 95% CI [–38.41, –35.63], dapagliflozin WMD –38.05?μmol/L, 95% CI [–44.47, –31.62], empagliflozin WMD –42.07?μmol/L, 95% CI [–46.27, –37.86]. The drug class effect of SUA reduction suggesting SGLT2 inhibitors might be beneficial for diabetic patients with hyperuricemia.     

Association between vitamin D receptor (FokI) genetic variant rs2228570 and iron profile in hemodialysis patients

Iron deficiency is a common etiology of anemia that causes suboptimal response to erythropoietin therapy in hemodialysis (HD) patients. This study investigated the association between vitamin D receptor (VDR) genetic variant (FokI) rs2228570 with iron indices (serum iron, transferrin, transferrin saturation, and ferritin). Sixty adequately hemodialyzed patients subdivided into two groups; 31 patients with transferrin saturation (TSAT)?<?20% and 29 with TSAT?>?20% who received I.V sodium ferric gluconate, calcium, and vitamin D. Sixty normal healthy were selected as the control group.. VDR genetic variant (SNP rs2228570) was genotyped in all subjects using PCR/RFLP. HD patients showed a higher frequency of rs2228570 FF genotype (38.3%) than controls (31.7%). The frequency of ff genotype and f allele in patients (8.4 and 35% respectively) were significantly lower than controls (25 and 46.7% respectively). Allele model (f vs. F): OR 0.721, 95% CI 0.521–0.998, P?=?0.049. While (ff vs. FF): OR 0.452, 95% CI 0.223–0.917, P = 0.028. The distribution of Ff?+?ff genotypes in HD cases with TSAT?>?20% was higher than in HD cases with TSAT?<?20%, Dominant model (Ff +ff vs FF): OR 2.753, 95% CI 1.902–3.409, P?=?0.048. f allele showed lower frequency in low TSAT group than high TSAT group (27.4 vs. 43.1%) with significant P value (P?=?0.042) with allele model (f vs. F): OR 2.012, 95% CI 1.923–4.226, P?=?0.042. Fok-1 ff, Ff?+?ff genotypes were significantly associated with TSAT?>?20% with a protective effect against low TSAT in HD patients.

     

Interleukin-12B rs3212227 polymorphism and cancer risk: a meta-analysis

IL-12 plays a very important role in the development and progress of cancer. IL-12B rs3212227 polymorphism has been reported and many studies have focused on the role of this polymorphism in various cancers. However, the association between IL-12B rs3212227 polymorphism and cancer risk remains controversial. Therefore, we performed a systematic meta-analysis to estimate the overall cancer risk associated with this gene polymorphism and to quantify any potential between-study heterogeneity. PubMed and Embase databases were searched for case–control studies published up to April 1, 2012 that investigated IL-12B rs3212227 polymorphism and cancer risk. Odds ratios (OR) with 95?% confidence intervals (95?% CI) were used to access the strength of this association. Heterogeneity among articles and publication bias were also verified. Ten studies with 2,954 cancer patients and 3,276 healthy controls were included. This meta-analysis showed that there was a significant association between IL-12B rs3212227 polymorphism and overall cancer risk (CC/AC vs AA: OR?=?1.32, 95?% CI?=?1.06–1.63). When stratified by cancer type, we found a significant increased risk in cervical and nasopharyngeal cancer (OR?=?1.34, 95?% CI?=?1.04–1.73; OR?=?2.03, 95?% CI?=?1.57–2.63, respectively). In the stratified analysis, we also observed a similar association in population-based studies (OR?=?1.34, 95?% CI?=?1.00–1.80), Asian populations (OR?=?1.33, 95 % CI?=?1.06–1.67) and European populations (OR?=?1.54, 95 % CI?=?1.04–2.28). According to the results of our meta-analysis, IL-12B rs3212227 polymorphism probably is associated with a high risk of cancer.     

Association of inflammatory and other immune markers with gallbladder cancer: Results from two independent case-control studies

Most gallbladder cancer (GBC) cases arise in the context of gallstones, which cause inflammation, but few gallstone patients develop GBC. We explored inflammation/immune-related markers measured in bile and serum in GBC cases compared to gallstone patients to better understand how inflammatory patterns in these two conditions differ. We measured 65 immune-related markers in serum and bile from 41 GBC cases and 127 gallstone patients from Shanghai, China, and calculated age- and sex-adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for GBC versus gallstones. We then focused on the markers that were significantly elevated in bile and serum to replicate the findings in serum from 35 GBC cases and 31 gallstone controls from Chile. Comparing the highest versus lowest quantile, 15 markers (23%) were elevated in both serum and bile from GBC versus gallstone patients in the Shanghai study (p < 0.05). The strongest OR was for CXCL8 (interleukin-8) in serum (96.8, 95% CI: 11.9–790.2). Of these 15 markers, 6 were also significantly elevated in serum from Chile (CCL20, C-reactive protein, CXCL8, CXCL10, resistin, serum amyloid A). Pooled ORs from Shanghai and Chile for these 6 markers ranged from 7.2 (95% CI: 2.8–18.4) for CXCL10 to 58.2 (95% CI: 12.4–273.0) for CXCL8. GBC is associated with inflammation above and beyond that generated by gallstones alone. This local inflammatory process is reflected systemically. Future longitudinal studies are needed to identify the key players in cancer development, which may guide translational efforts to identify individuals at high risk of developing GBC.     

Effect of circadian rhythm type on serum lipid levels in shift workers: A 5-year cohort study

We investigated how differences in circadian rhythm type affect the health of workers engaged in shift work. Employees, who were newly hired in a steel company between 2007 and 2011, received the Morningness–Eveningness Questionnaire (MEQ) survey. The target participants were 153 male shift workers who were not being treated with any antihyperlipidemic drugs and underwent periodic physical examinations including blood tests at least twice. According to the score of the MEQ at the time of joining the company, we classified the subjects into five types. Longitudinal changes in serum lipid level were estimated among the circadian rhythm types adjusted for age, BMI, and other covariates using a linear mixed model. The regression coefficient of total cholesterol level in the “definitely and moderately morning” group was ?17.83 (95% confidence interval (CI): ?33.42 to ?2.23), and in the “intermediate ‘group’ was ?16.84 [95% CI: ?30.40 to ?3.28], compared to the moderate evening type.” The total cholesterol level was higher in the moderately evening type than in any of the other groups. Between the Morningness–Eveningness (ME) type and Low-density lipoprotein (LDL) cholesterol levels, compared with the “moderately evening type” group, the regression coefficient in the “intermediate type” group was ?16.08 (95% CI: ?28.79 to ?3.37), and in the “definitely and moderately morning type” group was ?17.50 [95% CI: ?32.11 to ?2.88]. The “moderately evening type” group had a higher LDL cholesterol level than any of the other groups. Evening-type circadian rhythm type shift workers are more prone to elevated serum lipid levels.     

DNA methylation and expression profiles of the brain-derived neurotrophic factor (BDNF) and dopamine transporter (DAT1) genes in patients with schizophrenia

Methylation and expression profile of CpG islands were examined in the promoters of the brain-derived neurotrophic factor (BDNF) and dopamine transporter (DAT1) genes. These are well known to be involved in the pathophysiology of psychiatric disorders such as schizophrenia. Genomic DNA was extracted from peripheral blood of 80 patients with schizophrenia and 71 healthy controls. Methylation pattern was studied by Methylation-Specific PCR. RNA expression analysis was done on extracted RNA from blood samples from patients suffering from schizophrenia (n?=?17) and healthy controls (n?=?17). Frequency of the BDNF gene methylation was highlighted as a statistically significant relationship between cases and controls regarding decreased risk of disease in comparison to unmethylated patterns (OR?=?0.24; 95?% CI?=?1.11–0.50; P?=?0.00007). For the DAT1 gene, this relationship was insignificant in 61 cases (76.25?%) and 52 controls (73.23?%) (OR?=?1.17; 95?% CI?=?0.53–2.61). Estimates of relative gene expression revealed a statistically significant association of the BDNF gene between schizophrenic patients and healthy controls (Mean?±?SD: 13.3920?±?15.19 and 0.437?±?0.328, P?=?0.0001) respectively; however, it was not significant for the DAT1 gene. This first hand evidence, regarding BDNF and DAT1 gene methylation and their expression profile with risk of schizophrenia, indicated a significant function for the BDNF gene in the development of schizophrenia. However, further populations with large sample sizes need to be studied to verify the exact role of BDNF in mental disorders such as schizophrenia.     

The neurite outgrowth inhibitor Nogo-A promotes denervation in an amyotrophic lateral sclerosis model

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by motor neuron loss and muscle wasting. In muscles of ALS patients, Nogo-A-a protein known to inhibit axon regeneration-is ectopically expressed at levels that correlate with the severity of the clinical symptoms. We now show that the genetic ablation of Nogo-A extends survival and reduces muscle denervation in a mouse model of ALS. In turn, overexpression of Nogo-A in wild-type muscle fibres leads to shrinkage of the postsynapse and retraction of the presynaptic motor ending. This suggests that the expression of Nogo-A occurring early in ALS skeletal muscle could cause repulsion and destabilization of the motor nerve terminals, and subsequent dying back of the axons and motor neurons.