Female Hormone 17β-Estradiol Downregulated MMP-2 Expression and Upregulated A1PI Expression in Human Corneal Stromal Cells

Breaking Barriers: Unveiling Sex-Related Differences in Cerebrospinal Fluid Analysis-A Narrative Review

(1) Background: The recent emphasis on sexual and gender diversity's impact on human health underscores the need for tailored diagnostic and therapeutic approaches in neurology. The aim of this article is to conduct a narrative review of the available scientific literature on sex differences in cerebrospinal fluid analysis. (2) Methods: The literature search encompassed PubMed databases, focusing on cerebrospinal fluid analysis and sex differences, considering parameters like cerebrospinal fluid protein content, cell count, albumin quotient (QAlb) and intrathecal IgG synthesis. (3) Results: Nine articles from the past two decades were identified, revealing limited research in this area. Males consistently exhibited higher cerebrospinal fluid protein content and albumin quotient values across various pathologies and age groups. Consequently, males more frequently manifested blood-cerebrospinal fluid barrier dysfunction than females. No significant sex differences were observed in cerebrospinal fluid leukocyte count or intrathecal IgG synthesis. (4) Conclusions: This review highlights the dearth of research on sex differences in cerebrospinal fluid analysis, despite consistent findings of higher protein content and albumin quotient values in males. Revisiting current diagnostic thresholds based on sex is crucial for accurate prognosis and personalised treatment strategies in neurological disorders. Moving towards sex-specific approaches in clinical practice is imperative for advancing personalised medicine.

Cerebrospinal fluid/serum albumin ratio in patients with Lewy body disease: a systematic review and meta-analysis

Background

Abnormal cerebrospinal fluid (CSF)/serum albumin ratio (Qalb) levels have been observed in patients with cognitive impairment. Few studies have specifically focused on Lewy Body Disease (LBD), and the results were controversial. Thus, we conducted this systematic review and meta-analysis to investigate Qalb levels in patients with LBD by including data from different studies.

Method

We systematically searched PubMed, Embase, Cochrane Library, and Web of Science databases for a collection of studies containing studies comparing Qalb levels in patients with LBD and healthy controls (including healthy controls and other dementia subtypes). In the initial search, 86 relevant papers were retrieved. Standardized mean differences (SMD) in Qalb levels were calculated using a random effects model.

Results

A total of 13 eligible studies were included. Mean Qalb levels were significantly higher in patients with LBD compared to healthy older adults [standardized mean difference (SMD): 2.95, 95% confidence interval (CI): 0.89-5.00, Z = 2.81, p = 0.005]; and were significantly higher in patients with LBD than in patients with Alzheimer's disease (AD) (SMD: 1.13, 95% CI: 0.42-1.83, Z = 3.15, p = 0.002);whereas mean Qalb levels were significantly higher in patients with frontotemporal lobar degeneration (FTLD) compared to those with AD (SMD: 1.13, 95% CI,0.14-2.13, Z = 2.24, p = 0.03).

Conclusion

Qalb levels were significantly elevated in LBD patients compared with normal older adults and were higher than those in AD patients and FTLD patients, which helped in the differential diagnosis of LBD from other neurodegenerative diseases.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024496616.

Sex Differences in Albumin Quotient and Cerebrospinal Fluid Total Protein Content Do Not Depend on Anthropometric Factors

(1) Background: Cerebrospinal fluid (CSF)/serum albumin quotient (QAlb) and CSF total protein (TP) are more elevated in males than females, and this has been hypothesised to be due to anthropometric differences between the sexes. This study aimed to investigate QAlb and CSF TP as a function of body height, weight, and body mass index (BMI). (2) Methods: A total of 207 patients were included in the study and analysed blinded to clinical diagnosis. (3) Results: Multivariable linear regressions were run to predict log-transformed Qalb and log-transformed CSF TP value from age, sex, weight, and height (first model) or from age, sex, and BMI (second model). In both models, age (β = 0.004, 95% CI = 0.002 to 0.006) and sex (β = -0.095, 95% CI = -0.169 to -0.021, and β = -0.135, 95% CI = -0.191 to -0.079) were significant predictors for QAlb, but weight, height, and BMI were not. Similarly, age (β = 0.004, 95% CI = 0.003 to 0.006) and sex (β = -0.077, 95% CI = -0.142 to -0.013, and β = -0.109, 95% CI = -0.157 to -0.060) were significant predictors for CSF TP, while anthropometric characteristics were not. No differences in QAlb and CSF TP were found when grouping males and females by BMI status. (4) Conclusions: Our data suggest that anthropometric characteristics could not explain the sex-related differences in QAlb and CSF TP.

Implication of Central Nervous System Barrier Impairment in Amyotrophic Lateral Sclerosis: Gender-Related Difference in Patients

Central nervous system (CNS) barrier impairment has been reported in amyotrophic lateral sclerosis (ALS), highlighting its potential significance in the disease. In this context, we aim to shed light on its involvement in the disease, by determining albumin quotient (QAlb) at the time of diagnosis of ALS in a large cohort of patients. Patients from the university hospital of Tours (n = 307) were included in this monocentric, retrospective study. In total, 92 patients (30%) had elevated QAlb levels. This percentage was higher in males (43%) than in females (15%). Interestingly, QAlb was not associated with age of onset, age at sampling or diagnostic delay. However, we found an association with ALS functional rating scale-revised (ALSFRS-r) at diagnosis but this was significant only in males. The QAlb levels were not linked to the presence of a pathogenic mutation. Finally, we performed a multivariate survival analysis and found that QAlb was significantly associated with survival in male patients (HR = 2.3, 95% CI = 1.2-4.3, p = 0.009). A longitudinal evaluation of markers of barrier impairment, in combination with inflammatory biomarkers, could give insight into the involvement of CNS barrier impairment in the pathogenesis of the disease. The gender difference might guide the development of new drugs and help personalise the treatment of ALS.

The Sexual Dimorphism in Cerebrospinal Fluid Protein Content Does Not Affect Intrathecal IgG Synthesis in Multiple Sclerosis

(1) Background: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS) that mainly affects young adults and females more than males. The detection of intrathecal IgG synthesis (IIS) on cerebrospinal fluid (CSF) analysis supports the diagnosis of MS. A sexual dimorphism has recently been described in CSF protein content. (2) Methods: Clinical and laboratory data from 340 MS patients (F = 231, M = 99) and 89 people with clinically isolated syndrome (CIS) (F = 57, M = 32) were retrospectively analyzed to assess the presence of variables affected by sex and age. (3) Results: In MS, the albumin quotient (QAlb), reflecting the blood–CSF barrier (BCSFB) function, was higher in males (5.6 vs. 4.34) and correlated to age with a constant difference between sexes (F = 41.71). In CIS patients, QAlb increased with age only in males (r = 0.3567). Age was positively correlated to disease duration and severity in MS (r = 0.3502, r = 0.2986, respectively). No differences emerged for quantitative and qualitative IIS determinations. (4) Discussion: Although the main difference between males and females concerns the function of BCSFB assessed by QAlb, this sexual dimorphism does not affect the determination of the IIS evaluated both by quantitative and qualitative methods.

Evaluation of matrix metalloproteinase-9 plasma levels in untreated new Relapsing-remitting multiple sclerosis patients and their first-degree family

Matrix metalloproteinase, especially Matrix metalloproteinase-9 (MMP-9) has vital roles in the disruption of blood barrier, neuroinflammation and pathogenesis of multiple sclerosis (MS) patients. The goal of this study is to estimate the plasma levels of MMP-9 in the first-degree family of MS patients. 35 untreated patients with definite RRMS (Relapsing-Remitting Multiple sclerosis) according to the McDonald criteria, 24 healthy controls (HC) and 26 high-risk families of untreated RRMS patients were enrolled in the study. Plasma levels of MMP-9 were analyzed by ELISA (enzyme-linked immunosorbent assay). Although the plasma protein levels of MMP-9 were elevated significantly in the untreated RRMS group (P < 0.05, P = 0.0203) as compared to the control group, but the family of MS patients was not significance (P = 0.208). The mean plasma MMP-9 concentration for HC, untreated RRMS and high-risk group was 322.268 pg/ml, 611.926 pg/ml and 518.939 pg/ml respectively. MMP-9 was used to understand the role of this biomarker in the pathogenesis of MS in the high-risk group. It found that plasma levels of MMP-9 in the new cases of MS were increased considerably. Confirming the importance of MMP-9 as a predictive marker in the high-risk group will be needed more researches.

Sexual dimorphism in the cerebrospinal fluid total protein content

Objectives Cerebrospinal fluid (CSF) is a clear, colorless body fluid filling the central nervous system. The determination of the CSF total protein (TP) content represents an important screening test of various pathologies. We aimed to address the effect of sex and age on CSF-TP content and the use of the current upper reference limits (URLs). Methods CSF-TP content was analysed in a selected population of 1,252 patients (648 women and 604 men; age 18-89 years) who underwent lumbar puncture as a part of the diagnostic work-up. Samples presenting (i) more than 5 white blood cells (WBC)/µL, (ii) discolorations and (iii) reduced glucose were not included. Results The CSF-TP content median values were significantly higher in men than in women (46 vs. 37 mg/dL) even after adjusting for age and different hospital inpatients. CSF-TP content positively correlated with age both in men and in women with a constant difference between sexes of 8.5 mg/dL. Applying the most used URLs (mainly 45 and 50 mg/dL, but also 60 mg/dL), men received a laboratory report suggestive of altered CSF-TP content more frequently than women. The use of age- and sex-calibrated CSF-TP URLs reduced, but not eliminated, this sex-gap. Conclusions Using the current URLs, a condition of "elevated CSF-TP content" may be overestimated in men or, conversely, underestimated in women, regardless of the age and of the diagnosis. These results highlighted the need to apply CSF-TP URLs values ​​normalized for both sex and age.

Sex-Related Differences in Cerebrospinal Fluid Plasma-Derived Proteins of Neurological Patients

Background and aims: Cerebrospinal fluid (CSF) protein content presents a sexual dimorphism in humans. We investigated sex-related differences in CSF IgG levels and in the quantification of intrathecal IgG synthesis (IIS). Methods: CSF, serum albumin and IgG were measured in 1519 neurological patients and both linear and hyperbolic formulas were used for the quantification of IIS. CSF-restricted oligoclonal IgG bands (OCBs) were used as “gold standard”. Results: The linear IgG Index showed a weak agreement with OCBs in males and females (k = 0.559, k = 0.587, respectively), while the hyperbolic Reiber’s formulas had a moderate agreement with OCBs in females (k = 0.635) and a weak agreement in males (k = 0.565). Higher CSF albumin and IgG levels were found in men than in women in the whole population and in subjects without IIS after adjusting for age and for serum concentrations of albumin and IgG, respectively (Quade statistics, p < 0.000001). CSF and serum albumin and IgG levels positively correlated to age in both sexes. CSF total protein content did not correlate with CSF leukocyte numbers but was higher in patients with marked pleocytosis. Conclusions: In neurological patients, men have higher levels of CSF serum-derived proteins, such as albumin and IgG.

Regulation of matrix metalloproteinases 2 and 9 in corneal neovascularization

Corneal neovascularization (CNV), a pathological process of angiogenesis, can lead to serious consequences in the cornea. CNV is generally proved to associate with inflammation in the cornea closely, which is mainly elicited by the disruption of equilibrium between angiogenic and antiangiogenic factors. Angiogenic factors including vascular endothelial growth factors (VEGFs), basic fibroblast growth factors (bFGFs), and matrix metalloproteinases (MMPs) are vital factors in the formation of CNV. Especially VEGFs are convinced to be the core angiogenic factors in CNV, and MMPs are proved to exert dual effects on the process. Strikingly, matrix metalloproteinase 2 (MMP-2) and matrix metalloproteinase 9 (MMP-9) are determined to play key roles in the formation of CNV, while the mechanism is still vague. In this review, the latest researches are reviewed to discuss the role of MMP-2 and MMP-9 in CNV, respectively, and some inhibitors of them are presented. We hope to provide a new direction of drug research for CNV.

Increased age and male sex are independently associated with higher frequency of blood-cerebrospinal fluid barrier dysfunction using the albumin quotient

Background

The cerebrospinal fluid (CSF)/serum quotient of albumin (QAlb) is the most used biomarker for the evaluation of blood–cerebrospinal fluid barrier (B-CSF-B) permeability. For years QAlb was considered only as an age-related parameter but recently it has also been associated to sex. The aim of the present study was to explore the impact of sex in the determination of B-CSF-B dysfunction.

Methods

The analysis was retrospectively conducted on subjects consecutively admitted to the neurological ward. CSF and serum albumin levels were measured by immunonephelometry and pathological QAlb thresholds were considered: 6.5 under 40 years, 8.0 in the age 40–60 and 9.0 over 60 years.

Results

1209 subjects were included in the study. 718 females and 491 males (age: 15–88 years): 24.6% of patients had a diagnosis of multiple sclerosis, 23.2% suffered from other inflammatory neurological diseases, 24.6% were affected by non-inflammatory neurological diseases, and for 27.6% of patients the final neurological diagnosis could not be traced. Dysfunctional B-CSF-B was detected more frequently (44 vs. 20.1%, p < 0.0001) and median QAlb value were higher (7.18 vs. 4.87, p < 0.0001) in males than in females in the overall study population and in all disease subgroups. QAlb and age were positively correlated both in female (p < 0.0001) and male (p < 0.0001) patients, however the slopes of the two regression lines were not significantly different (p = 0.7149), while the difference between the elevations was extremely significant (p < 0.0001) with a gap of 2.2 units between the two sexes. Finally, in a multivariable linear regression analysis increased age and male sex were independently associated with higher QAlb in the overall study population (both p < 0.001) and after stratification by age and disease group.

Conclusions

Accordingly, identification and validation of sex-targeted QAlb thresholds should be considered as a novel tool in an effort to achieve more precision in the medical approach.

Multiplex Matrix Metalloproteinases Analysis in the Cerebrospinal Fluid Reveals Potential Specific Patterns in Multiple Sclerosis Patients

Background: Matrix metalloproteinases (MMPs) are pleiotropic enzymes involved in extracellular protein degradation and turnover. MMPs are implicated in the pathogenesis of many neurological diseases, including multiple sclerosis (MS).

Objective: To search the level of MMPs in the cerebrospinal fluid (CSF) of MS patients and detect possible disease-specific patterns.

Methods: CSF samples from 32 MS patients and, from 15 control subjects with other inflammatory neurological diseases (OIND) were analyzed. The Bio-Plex Pro Human MMP 9-Plex Panel (Bio-Rad) was used for the quantification of MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-10, MMP-12, and MMP-13.

Results: CSF MMP-1 and MMP-12 levels were significantly reduced in MS as compared with OIND. In MS patients' CSF: (i) MMP-1 levels were significantly higher in women vs. men; (ii) MMP-10 concentrations were higher in patients with CSF-restricted IgG oligoclonal bands, and (iii) MMP-7 levels were increased in patients with longer disease duration. In the OIND group MMP-7 and MMP-12 levels significantly and directly correlated with age.

Conclusions: Our study contributes to investigating the role of MMPs in MS, with regard to CSF immunological features and disease duration. Sex-specific differences were also detected in MMPs CSF levels.

RNA sequencing and differential expression reveals the effects of serial oestrus synchronisation on ovarian genes in dairy goats

A total of 24 female Xinong Saanen dairy goats were used to examine differentially expressed genes (DEGs) in the ovaries of goats treated once or three times for oestrus synchronisation (ES). The goats were randomly divided into two groups: one group received three ES treatments at fortnightly intervals (repeated or triple ES group), whereas the other was only treated once on the same day as the third ES treatment for the triple group (control group) during the breeding season. Ovaries of three goats in oestrus from each group were collected for morphological examination and transcriptome sequencing, while the rest of the goats were artificially inseminated twice. Litter size and fecundity rate tended (P = 0.06) to be lower in the triple ES group. A total of 319 DEGs were identified, including carbohydrate sulphotransferase 8 (CHST8), corticosteroid-binding globulin (CBG), oestradiol 17-β-dehydrogenase 1 (DHB1), oestrogen receptor 1 (ESR1), progestin and adipoQ receptor family member 4 (PAQR4), PAQR9, prostacyclin synthase (PTGIS), contactin-associated protein (CNTNAP4), matrix metalloproteinase-2 (MMP-2), regulator of G-protein signalling 9-2 (RGS9-2) and sperm surface protein Sp17 (Sp17); these were the most promising novel candidate genes for reproductive performances in goats. Our study indicates that triple ES could cause DNA damage and alter gene expression in goat ovaries, potentially affecting ovary function, neural regulation and hormone secretion.