Plasma levels of matrix metalloproteinase-9 (MMP-9) are associated with cognitive performance in patients with schizophrenia

Elevated plasma matrix metalloproteinase 9 in schizophrenia patients associated with poor antipsychotic treatment response and white matter density deficits

Oxidative stress and neuroinflammation contribute to schizophrenia (SCZ) pathology and may influence treatment efficacy. Matrix metalloproteinase 9 (MMP9) is a critical molecular node mediating the interaction between oxidative stress and inflammation, and so may influence treatment efficacy. Here we examined the associations of plasma MMP9 concentration with antipsychotic drug responses, clinical symptoms, and brain structure. A total of 129 healthy controls and 124 patients with SCZ were included in this study. Patients were monitored clinically during 8 weeks of antipsychotic treatment and classified as poor responders (n = 49) or good responders (n = 75). We then compared plasma MMP9 concentrations in healthy controls at baseline and both SCZ responder groups at baseline and after the 8-week antipsychotic treatment regimen. Cognitive function was also examined using the MATRICS Consensus Cognitive Battery. In addition, we extracted regional white matter density from magnetic resonance images of patients. Compared to healthy controls, plasma MMP9 levels were significantly elevated in poor responders at baseline and negatively correlated with both white matter density in the right superior temporal gyrus and the change in cognitive symptoms after treatment. Conversely, there was no significant difference in plasma MMP9 between good responders and healthy controls, and no associations of plasma MMP9 with cognitive symptoms or regional white matter density among good responders. Elevated plasma MMP9 is associated with poor antipsychotic drug efficacy and white matter deficits in SCZ patients, and so may be a useful biomarker to guide personalized treatment.

Matrix metalloproteinase 9 (MMP-9) activity, hippocampal extracellular free water, and cognitive deficits are associated with each other in early phase psychosis

Increasing evidence points toward the role of the extracellular matrix, specifically matrix metalloproteinase 9 (MMP-9), in the pathophysiology of psychosis. MMP-9 is a critical regulator of the crosstalk between peripheral and central inflammation, extracellular matrix remodeling, hippocampal development, synaptic pruning, and neuroplasticity. Here, we aim to characterize the relationship between plasma MMP-9 activity, hippocampal microstructure, and cognition in healthy individuals and individuals with early phase psychosis. We collected clinical, blood, and structural and diffusion-weighted magnetic resonance imaging data from 39 individuals with early phase psychosis and 44 age and sex-matched healthy individuals. We measured MMP-9 plasma activity, hippocampal extracellular free water (FW) levels, and hippocampal volumes. We used regression analyses to compare MMP-9 activity, hippocampal FW, and volumes between groups. We then examined associations between MMP-9 activity, FW levels, hippocampal volumes, and cognitive performance assessed with the MATRICS battery. All analyses were controlled for age, sex, body mass index, cigarette smoking, and years of education. Individuals with early phase psychosis demonstrated higher MMP-9 activity (p < 0.0002), higher left (p < 0.05) and right (p < 0.05) hippocampal FW levels, and lower left (p < 0.05) and right (p < 0.05) hippocampal volume than healthy individuals. MMP-9 activity correlated positively with hippocampal FW levels (all participants and individuals with early phase psychosis) and negatively with hippocampal volumes (all participants and healthy individuals). Higher MMP-9 activity and higher hippocampal FW levels were associated with slower processing speed and worse working memory performance in all participants. Our findings show an association between MMP-9 activity and hippocampal microstructural alterations in psychosis and an association between MMP-9 activity and cognitive performance. Further, more extensive longitudinal studies should examine the therapeutic potential of MMP-9 modulators in psychosis.

System biology approaches to identify hub genes linked with ECM organization and inflammatory signaling pathways in schizophrenia pathogenesis

Schizophrenia (SZ) is a chronic and devastating mental illness that affects around 20 million individuals worldwide. Cognitive deficits and structural and functional changes of the brain, abnormalities of brain ECM components, chronic neuroinflammation, and devastating clinical manifestation during SZ are likely etiological factors shown by affected individuals. However, the pathophysiological events associated with multiple regulatory pathways involved in the brain of this complex disorder are still unclear. This study aimed to develop a pipeline based on bioinformatics and systems biology approaches for identifying potential therapeutic targets involving possible biological mechanisms from SZ patients and healthy volunteers. About 420 overlapping differentially expressed genes (DEGs) from three RNA-seq datasets were identified. Gene ontology (GO), and pathways analysis showed several biological mechanisms enriched by the commonly shared DEGs, including extracellular matrix organization (ECM) organization, collagen fibril organization, integrin signaling pathway, inflammation mediated by chemokines and cytokines signaling pathway, and GABA-B receptor II and IL4 mediated signaling. Besides, 15 hub genes (FN1, COL1A1, COL3A1, COL1A2, COL5A1, COL2A1, COL6A2, COL6A3, MMP2, THBS1, DCN, LUM, HLA-A, HLA-C, and FBN1) were discovered by comprehensive analysis, which was mainly involved in the ECM organization and inflammatory signaling pathway. Furthermore, the miRNA target of the hub genes was analyzed with the random-forest-based approach software miRTarBase. In addition, the transcriptional factors and protein kinases regulating overlapping DEGs in SZ, namely, SUZ12, EZH2, TRIM28, TP53, EGR1, CSNK2A1, GSK3B, CDK1, and MAPK14, were also identified. The results point to a new understanding that the hub genes (fibronectin 1, collagen, matrix metalloproteinase-2, and lumican) in the ECM organization and inflammatory signaling pathways may be involved in the SZ occurrence and pathogenesis.

MMP-9 plasma level as biomarker of cochlear implantation outcome in cohort study of deaf children

PURPOSE

If before cochlear implantation it was possible to assay biomarkers of neuroplasticity, we might be able to identify those children with congenital deafness who, later on, were at risk of poor speech and language rehabilitation outcomes.

METHODS

A group of 40 children aged up to 2 years with DFNB1-related congenital deafness was observed in this prospective cohort study over three follow-up intervals (0, 8, and 18 months) after cochlear implant (CI) activation. Children were assessed for auditory development using the LittlEARS Questionnaire (LEAQ) score, and at the same time, measurements were made of matrix metalloproteinase-9 (MMP-9) plasma levels.

RESULTS

There were significant negative correlations between plasma levels of MMP-9 at 8-month follow-up and LEAQ score at cochlear implantation (p = 0.04) and LEAQ score at 18-month follow-up (p = 0.02) and between MMP-9 plasma levels at 18-month follow-up and LEAQ score at cochlear implantation (p = 0.04). As already reported, we confirmed a significant negative correlation between MMP-9 plasma level at cochlear implantation and LEAQ score at 18-month follow-up (p = 0.005). Based on this latter correlation, two clusters of good and poor CI performers could be isolated.

CONCLUSIONS

The study shows that children born deaf who have an MMP-9 plasma level of less than 150 ng/ml at cochlear implantation have a good chance of attaining a high LEAQ score after 18 months of speech and language rehabilitation. This indicates that MMP-9 plasma level at cochlear implantation is a good prognostic marker for CI outcome.

Levels of Matrix Metalloproteinase 9 Are Elevated in Persons With Schizophrenia or Bipolar Disorder: The Role of Modifiable Factors

Background

Matrix metalloproteinases (MMPs) are a diverse set of enzymes associated with inflammation. MMP-9 is of particular interest because it has been associated with autoimmune and cardiopulmonary disorders, tobacco smoking, and obesity, prevalent in psychiatric populations.

Methods

Sensitive enzyme immunoassays measured MMP-9 in blood samples from 1121 individuals (mean age = 35.6 [SD = 13.0] years; 47.7% male; 440 with schizophrenia, 399 with bipolar disorder, and 282 without a psychiatric disorder). We estimated the odds of diagnosis associated with MMP-9, demographic variables, tobacco smoking, and obesity, and also the partial explained variance using regression methods. We also determined the association between psychiatric medications and MMP-9 levels.

Results

Individuals with elevated MMP-9 levels had higher odds of schizophrenia or bipolar disorder compared with the nonpsychiatric group adjusted for demographic variables. Partial correlation analyses indicated the demographic-adjusted variance associated with MMP-9, smoking, obesity, and their interaction explained 59.6% for schizophrenia and 39.9% for bipolar disorder. Levels of MMP-9 were substantially lower in individuals receiving valproate, particularly relatively high doses.

Conclusions

Individuals with higher levels of MMP-9 have significantly higher odds of schizophrenia or bipolar disorder. Individuals receiving valproate had substantially lower levels of MMP-9, possibly related to its ability to inhibit histone deacetylation. A substantial portion of the variance in clinical disorders associated with MMP-9 can be attributed to smoking or obesity. Interventions to reduce smoking and obesity might reduce the morbidity and mortality associated with elevated MMP-9 levels and improve the health outcomes of individuals with these disorders.

Vascular-related biomarkers in psychosis: a systematic review and meta-analysis

Background

While the molecular underpinnings of vascular dysfunction in psychosis are under active investigation, their implications remain unclear due to inconsistent and sometimes sparse observations. We conducted a comprehensive meta-analysis to critically assess the alterations of vascular-related molecules in the cerebrospinal fluid (CSF) and blood of patients with psychotic disorders compared with healthy individuals.

Methods

Databases were searched from inception to February 23, 2023. Meta-analyses were performed using a random-effects model. Meta-regression and subgroup analyses were conducted to assess the effects of clinical correlates.

Results

We identified 93 eligible studies with 30 biomarkers investigated in the CSF and/or blood. Among the biomarkers examined, psychotic disorders were associated with elevated CSF-to-serum albumin ratio (standardized mean difference [SMD], 0.69; 95% confidence interval [CI], 0.35-1.02); blood S100B (SMD, 0.88; 95% CI, 0.59-1.17), matrix metalloproteinase-9 (MMP-9; SMD, 0.66; 95% CI, 0.46-0.86), and zonulin (SMD, 1.17; 95% CI, 0.04-2.30). The blood levels of S100B, MMP-9, nerve growth factor (NGF), vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1), and vascular adhesion molecule 1 (VCAM-1) were altered in patient subgroups differing in demographic and clinical characteristics. Blood S100B level was positively correlated with age and duration of illness. Substantial between-study heterogeneity was observed in most molecules.

Conclusion

The alterations in certain vascular-related fluid markers in psychotic disorders suggest disturbances in normal vascular structures and functions. However, not all molecules examined displayed clear evidence of changes. While potential impacts of clinical factors, including the administered treatment, were identified, the exploration remained limited. Further studies are needed to investigate the diverse patterns of expression, and understand how these abnormalities reflect the pathophysiology of psychosis and the impact of clinical factors.

PECULIARITIES OF DYNAMICS OF INDICATORS OF PROTEINS OXIDATIVE MODIFICATION AND MATRIX METALLOPROTEINASE-9 ACTIVITY IN PATIENTS WITH PARANOID SCHIZOPHRENIA DEPENDING ON THE DISEASE DURATION

OBJECTIVE

The aim: The objective of the research was to study the indicators of oxidative modification of proteins (OMP) and the activity of matrix metalloproteinase-9 (MMP-9) in patients with paranoid schizophrenia depending on the disease duration.

PATIENTS AND METHODS

Materials and methods: 320 patients were included in the examination. 20 patients were with "Primary psychotic episode" (Comparison Group) and 300 patients were diagnosed with "Paranoid schizophrenia" (Experimental Group): 60 of them have suffered from this disease for a duration from 3 to 5 years (Subgroup I ); 60 patients have suffered for a period from 6 to 10 years (Subgroup II); 60 individuals - from 11 to 15 years (Subgroup III); 60 patients have suffered for a duration from 16 to 20 years (Subgroup IV); 60 patients - from 21 years and longer (Subgroup V).

RESULTS

Results: The presented data showed that the levels of OMP indicators in Subgroup I constituted 0.826±0.046 conventional units at a wavelength of 356 nm; 0.864±0.051 conventional units at a wavelength of 370 nm; 0.444±0.019 conventional units at a wavelength of 430 nm; 0.176±0.007 conventional units at a wavelength of 530 nm, which is 1.99; 1.6; 1.13 and 1.43 times higher than in the Comparison Group. The content of OMP products was higher by 2.24; 1.74; 1.17, and 1.43 times in Subgroup II, respectively, by 2.4; 1.80; 1.36 and 1.46 times in Subgroup III, respectively; by 2.5; 1.9; 1.4; 1.6 times in Subgroup IV, respectively; by 2.5; 2.02; 1.54; 1.7 times in Subgroup V, respectively. The conducted correlation analysis indicated a direct correlation between OMP indicators and the disease duration. The concentration of MMP-9 in the patients of the Comparison Group was equal to 892.84±87.80 pg/ml, which was 11.2% less compared to the Experimental Subgroup I, where this indicator was 992.84±67.50 pg/ml. MMP-9 constituted 1092.53±47.20 pg/ml on average in the patients of Subgroup II, which was 22.36% higher than in the Comparison Group. This indicator was 1702.84±37.60 pg/ml in Subgroup III, which was 90.7% higher than in the Comparison Group. It constituted 1492.84±47.29 pg/ml in Subgroup IV, which was 67.2% higher than in the Comparison Group; and 2037.21±57.80 pg/ ml in Subgroup V, which was more than two times higher than in the Comparison Group (p<0.05). The conducted correlation analysis showed a direct relation between MMP-9 expression and the increase in OMP indicators. This relation was more significant between MMP-9 and OMP products of a neutral nature. The correlation strength between MMP-9 and OMP products of a basic nature was somewhat less significant.

CONCLUSION

Conclusions: According to the results of the conducted analysis, the examined patients had the signs of decompensation of reactive-adaptive biomolecular mechanisms which activated radical reactions with the subsequent accumulation of oxidation products.

Abnormal synaptic plasticity and impaired cognition in schizophrenia

Schizophrenia (SCZ) is a severe mental illness that affects several brain domains with relation to cognition and behaviour. SCZ symptoms are typically classified into three categories, namely, positive, negative, and cognitive. The etiology of SCZ is thought to be multifactorial and poorly understood. Accumulating evidence has indicated abnormal synaptic plasticity and cognitive impairments in SCZ. Synaptic plasticity is thought to be induced at appropriate synapses during memory formation and has a critical role in the cognitive symptoms of SCZ. Many factors, including synaptic structure changes, aberrant expression of plasticity-related genes, and abnormal synaptic transmission, may influence synaptic plasticity and play vital roles in SCZ. In this article, we briefly summarize the morphology of the synapse, the neurobiology of synaptic plasticity, and the role of synaptic plasticity, and review potential mechanisms underlying abnormal synaptic plasticity in SCZ. These abnormalities involve dendritic spines, postsynaptic density, and long-term potentiation-like plasticity. We also focus on cognitive dysfunction, which reflects impaired connectivity in SCZ. Additionally, the potential targets for the treatment of SCZ are discussed in this article. Therefore, understanding abnormal synaptic plasticity and impaired cognition in SCZ has an essential role in drug therapy.

Matrix metalloproteinase-3 serum levels in schizophrenic patients

OBJECTIVES

It has been reported that matrix metalloproteinase, MMP-3 may play a significant role in the pathophysiology of mental disorders. However, there are no data on the level of MMP-3 in people suffering from schizophrenia, or its influence on the mental state of these people. The aim of this study was to investigate the effect of an antipsychotic treatment on the blood levels of MMP-3, as well as investigating its relationship with insight into schizophrenia.

METHODS

Thirty people with schizophrenia were included in the study. The concentration of MMP-3 in the blood serum was assessed using enzyme-linked immunosorbent assay. Insight into the disease was assessed using the Beck Cognitive Insight Scale.

RESULTS

The antipsychotic treatment applied decreased the levels of MMP-3 in patients with schizophrenia (p = 0.005), however, the statistically significant interaction (p = 0.02) indicates that the decrease only concerned men. There was also a statistically significant correlation between the level of MMP-3 and insight into the disease (p = 0.02).

CONCLUSION

MMP-3 may be associated with gender, treatment and symptoms in schizophrenic patients.KEY POINTSMMP3 could be used as a potential biomarker for schizophrenia.The level of MMP-3 decreased due to the applied antipsychotic treatment.The higher the level of MMP-3 in a group of people with schizophrenia, the better insight into their disease.

Prospective cohort study reveals MMP-9, a neuroplasticity regulator, as a prediction marker of cochlear implantation outcome in prelingual deafness treatment

Because of vast variability of cochlear implantation outcomes in prelingual deafness treatment, identification of good and poor performers remains a challenging task. To address this issue, we investigated genetic variants of matrix metalloproteinase 9 (MMP9) and brain-derived neurotrophic factor (BDNF) and plasma levels of MMP-9, BDNF, and pro-BDNF that have all been implicated in neuroplasticity after sensory deprivation in the auditory pathway. We recruited a cohort of prelingually deaf children, all implanted before the age of 2, and carried out a prospective observation (N = 61). Next, we analyzed the association between (i) functional MMP9 (rs20544, rs3918242, rs2234681) and BDNF (rs6265) gene variants (and their respective protein levels) and (ii) the child’s auditory development as measured with the LittlEARS Questionnaire (LEAQ) before cochlear implant (CI) activation and at 8 and 18 months post-CI activation. Statistical analyses revealed that the plasma level of MMP-9 measured at implantation in prelingually deaf children was significantly correlated with the LEAQ score 18 months after CI activation. In the subgroup of DFNB1-related deafness (N = 40), rs3918242 of MMP9 was significantly associated with LEAQ score at 18 months after CI activation; also, according to a multiple regression model, the ratio of plasma levels of pro-BDNF/BDNF measured at implantation was a significant predictor of overall LEAQ score at follow-up. In the subgroup with DFNB1-related deafness, who had CI activation after 1 year old (N = 22), a multiple regression model showed that rs3918242 of MMP9 was a significant predictor of overall LEAQ score at follow-up.

Matrix metalloproteinase-9 increases the risk of cognitive impairment in schizophrenia

PURPOSE OF THE ARTICLE

Synaptic plasticity is known to play role in pathogenesis of schizophrenia. Cognitive impairment is one of the complications of schizophrenia, leading to poor quality of life. Matrix metalloprotease-9 (MMP-9) and neurotrophin-3 (NT-3) are markers of synaptic plasticity, widely investigated in neuropsychiatric disorders. The objective of the study was to investigate the levels of MMP-9 and NT-3 and their association with cognitive impairment in schizophrenia.

MATERIAL AND METHODS

124 schizophrenia patients and 124 controls were enrolled in the study. MMP-9 and NT-3 were estimated in both the groups using ELISA. Cognition was assessed using Addenbrooke cognitive examination-III (ACE-III) and disease severity was assessed using PANSS.

RESULTS

MMP-9 (p = .003) and NT -3 (p < .001) were found to be elevated in schizophrenia cases compared to controls. There was significant association of MMP-9 with fluency (r = -0.195, p = .030), language (r = -0.196, p = .029) and total ACE-III scores (r = -0.197, p = .029). Also we observed that MMP-9 increases the risk of cognitive impairment in schizophrenia patients (OR = 2.509, CI= 1.215 - 5.18, p = .013).

CONCLUSION

MMP-9 and NT-3 are elevated in schizophrenia. MMP-9 was associated with fluency and language component of cognition and increases the risk of cognitive impairment in schizophrenia.

Matrix Metalloproteinase 9 Blood Alterations in Patients With Schizophrenia Spectrum Disorders: A Systematic Review and Meta-Analysis

BACKGROUND

Matrix metalloproteinase 9 (MMP-9), an extracellular network protease implicated in glutamatergic signaling, may be part of the pathophysiology of schizophrenia spectrum disorders (SSD).

METHODS

We performed a systematic review in PubMed/Embase until July 15, 2020, conducting a random-effects meta-analysis of studies comparing MMP-9 blood levels in SSD vs healthy controls (HCs) and psychiatric controls (PCs), calculating between-group differences in standardized mean differences (SMDs) ± 95% confidence intervals (CIs). Meta-regression analyses included sex, age, illness duration, antipsychotic dose, and Positive and Negative Syndrome Scale (PANSS) total/subscales. Subgroup analyses included first-episode patients (FEP) vs non-FEP, each vs HCs and vs PCs, and blood sample type. Study quality was assessed using the Newcastle-Ottawa scale.

RESULTS

Four, five, and two trials were rated as high, fair, and low quality. In 11 studies (n = 1443), 643 patients (age = 36.7 ± 14.1 years, females = 42.9%) were compared with HCs (n = 631), with 4 studies including also 169 PCs. MMP-9 levels were higher in SSD vs HCs (SMD = 0.52, 95%CI = 0.20-0.85, P = .002), but not in PCs vs HCs (n = 132, after removing one implausible outlier [SMD = 0.33, 95%CI = -0.16 to 0.85, P = .082]). MMP-9 differences between SSD and HCs were associated with higher PANSS total (coefficient = 0.02, 95%CI = 0.01-0.02, P < .001), PANSS positive (coefficient = 0.08, 95%CI = 0.02-0.13, P = .006), and PANSS general scores (coefficient = 0.02, 95%CI = 0.01-0.03, P < .001). MMP-9 level differences vs HCs did not vary significantly between FEP (n = 103, SMD = 0.44, 95%CI = 0.15-0.72, P = .71) and non-FEP patients (n = 466, SMD = 0.59, 95%CI = 0.38-0.80; P = .34) (FEP vs non-FEP: P = .39). In four high-quality studies, MMP-9 levels remained significantly higher in SSD vs HCs (SMD = 0.82, 95%CI = 0.03-1.61).

CONCLUSIONS

Findings suggest MMP-9 upregulation in SSD, requiring further validation and understanding of related pathways.

Plasma levels of matrix metalloproteinase-9 (MMP-9) are associated with cognitive performance in patients with schizophrenia

Aim

Matrix metalloproteinase‐9 (MMP‐9) has been shown to modulate synaptic plasticity and may contribute to the pathophysiology of schizophrenia. This study investigated the peripheral levels of MMP‐9 and its association with cognitive functions in patients with schizophrenia to see the possible involvement of MMP‐9 in pathophysiology of schizophrenia, especially in cognitive decline.

Methods

We measured the plasma levels of MMP‐9 in 257 healthy controls and 249 patients with schizophrenia, including antipsychotic drug–free patients. We also explored the possible association between plasma MMP‐9 levels and cognitive performance in healthy controls and patients with schizophrenia using the Wechsler Adult Intelligence Scale, Third Edition (WAIS‐ III), the Wechsler Memory Scale‐Revised (WMS‐R), and the Rey Auditory Verbal Learning Test (AVLT).

Results

We found that the plasma levels of MMP‐9 were significantly higher in patients with schizophrenia, including antipsychotic drug–free patients, than in healthy controls. We found a significant negative association between plasma MMP‐9 levels and cognitive performance in controls and patients with schizophrenia.

Conclusion

Together, these convergent data suggest a possible biological mechanism for schizophrenia, whereby increased MMP‐9 levels are associated with cognitive impairment.

Plasma levels of MMP‐9 were significantly higher in patients with schizophrenia and significant negative association between plasma MMP‐9 levels and cognitive performance was observed in controls and patients with schizophrenia.