{
  "abstract": "Background: Synaptic dysfunction and immune mechanisms are both implicated in schizophrenia. Annexin A1 (ANXA1) is a glucocorticoid-induced pro-resolving protein and neurogranin (Ng) is a post-synaptic, calmodulin-binding protein studied as a peripheral correlate of synaptic biology. Circulating ANXA1 has not previously been measured in schizophrenia, and serum Ng is sparsely characterised, so no directional hypothesis was pre-specified.\n\nMethods: In a single-centre case–control study, 35 patients meeting DSM-5 criteria for schizophrenia (diagnosed with the SCID-5) and 35 sex-comparable healthy controls were enrolled. Fasting serum ANXA1 and Ng were measured in duplicate by sandwich enzyme-linked immunosorbent assay. Symptom severity was rated with the PANSS and CGI-S, and antipsychotic treatment was documented including chlorpromazine equivalents. The pre-specified primary analysis was the Mann–Whitney U test for each biomarker, with Bonferroni and false-discovery-rate correction; group differences were then adjusted for age, sex and body-mass index by analysis of covariance. All other analyses were exploratory.\n\nResults: Both biomarkers were lower in patients: ANXA1 median 6.21 (IQR 5.12–8.34) vs. 13.06 (8.82–23.66) ng/mL (U = 309, p = 3.6 × 10⁻⁴; rank-biserial r = − 0.50) and Ng 174.2 (149.1–281.0) vs. 380.0 (237.1–547.1) pg/mL (U = 302, p = 2.7 × 10⁻⁴; r = − 0.51). Both remained significant after correction for multiple testing and in ANCOVA adjusted for age, sex and body-mass index (adjusted difference − 6.71 ng/mL, p = 0.011; −182.3 pg/mL, p = 0.0008). Neither biomarker was associated with chlorpromazine-equivalent dose, clozapine use, antipsychotic polypharmacy, long-acting injectable use or lifetime electroconvulsive therapy. The two proteins correlated strongly in patients (r = 0.900) and controls (r = 0.844), with no significant between-group difference in the correlation (Fisher r-to-z, p = 0.339), and neither tracked PANSS or CGI-S. Sex-stratified differences reached significance in women only, but the group × sex interaction was not significant.\n\nConclusions: Serum ANXA1 and neurogranin were lower in chronic schizophrenia and showed no statistically significant association with the treatment variables measured, although medication effects cannot be excluded in a uniformly medicated sample. Because no inflammatory, central or longitudinal measures were obtained, these exploratory findings cannot demonstrate impaired resolution of inflammation, altered central synaptic integrity, or trait status; they identify two candidate peripheral markers that require replication.\n\nSupplementary Information: The online version contains supplementary material available at https://doi.org/10.1186/s12888-026-08822-3.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Psychiatry, Faculty of Medicine, Gaziantep University, Gaziantep, Turkey",
    "Department of Biochemistry, Faculty of Medicine, Gaziantep University, Gaziantep, Turkey"
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 8,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Muhammet Sancaktar",
      "orcid": "0000-0002-4209-2885"
    },
    {
      "affs": [
        0
      ],
      "name": "Bahadır Demir",
      "orcid": "0000-0003-2798-6255"
    },
    {
      "affs": [
        0
      ],
      "name": "Ekin Nur Yağdıran",
      "orcid": "0009-0004-7187-4781"
    },
    {
      "affs": [
        0
      ],
      "name": "Gülçin Elboğa",
      "orcid": "0000-0003-3903-1835"
    },
    {
      "affs": [
        0
      ],
      "name": "Feridun Bülbül",
      "orcid": "0000-0002-8307-9273"
    },
    {
      "affs": [
        1
      ],
      "name": "Kenan Ercan",
      "orcid": "0000-0002-9578-536X"
    },
    {
      "affs": [
        1
      ],
      "name": "Seyithan Taysı",
      "orcid": "0000-0003-1251-3148"
    },
    {
      "affs": [
        0
      ],
      "name": "Abdurrahman Altındağ",
      "orcid": "0000-0001-5531-4419"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dqkqhc49f5nqh.bib",
  "cited_by": 0,
  "doi": "10.1186/s12888-026-08822-3",
  "fulltext_url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC13711958/",
  "id": "dqkqhc49f5nqh",
  "issns": [
    "1471-244X"
  ],
  "landing_url": "https://doi.org/10.1186/s12888-026-08822-3",
  "language": "en",
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "heading",
      "Research"
    ],
    [
      "openalex",
      "2738|Schizophrenia research and treatment"
    ]
  ],
  "openalex": "W7223861867",
  "pdf_url": null,
  "pmcid": "PMC13711958",
  "pmid": "42947046",
  "published": "2026-10-27",
  "publisher": "BMC",
  "ris": "https://research.draconitic.com/paper/dqkqhc49f5nqh.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T12:22:38Z",
      "native_id": "PMC13711958",
      "source": "pmc",
      "url": "https://doi.org/10.1186/s12888-026-08822-3"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2738|Schizophrenia research and treatment",
      "subfield": "psychiatry"
    }
  ],
  "title": "Lower serum annexin A1 and neurogranin levels in chronic schizophrenia: a case–control study",
  "title_text": "Lower serum annexin A1 and neurogranin levels in chronic schizophrenia: a case–control study",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T12:22:38Z",
  "url": "https://research.draconitic.com/paper/dqkqhc49f5nqh",
  "venue": "BMC Psychiatry",
  "versions": []
}