Activity of matrix metallo proteinases (MMPs) and the tissue inhibitor of MMP (TIMP)-1 in electromagnetic field-exposed THP-1 cells.

Journal of cellular physiology · 2012 · Mixed · Low evidence

← Research stream

MixedLow evidencePaper 4552

THP-1 cells exposed to a 50 Hz, 1 mT EMF for 24 h showed reduced anti-oxidant enzyme activity and increased nitrogen intermediates involving the iNOS pathway. The study examined whether nitration of TIMP-1 could contribute to increased MMP activity in EMF-exp…

Study snapshot

PublicationJournal of cellular physiology · 2012

Study typein_vitro

Reported directionMixed

Evidence ratingLow

Abstract

Matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) are the main determinants of tissue remodeling in both physiological and pathological processes. Metabolic processes, which generate oxidants and antioxidants can be influenced by environmental factors such as electromagnetic fields (EMF). We analyzed the effects of EMF on the activity and expression of MMPs in THP-1 cells. Cells were exposed to a 50 Hz, 1 mT EMF for 24 h and incubated with or without LPS. Our data indicate that THP-1 cells exposed to EMF causes a reduction of anti-oxidant enzyme activity and an enhancement of nitrogen intermediates involving the iNOS pathway. We then analyzed the role of nitration of TIMP-1 in increasing the activity of MMPs in EMF exposed cells. Molecular modeling tools were employed to identify the most plausible sites in the active conformation of TIMP-1; at least two protein sites, Y120 and Y38 and/or Y72 were identified. Reactive nitrogen species (RNS) may affect protein targets, such as TIMP-1, which are crucial for the regulation of MMP activities by oxidation of sulfydryl groups, or by nitration of tyrosine residues. These results may suggest a pathway connecting an imbalance of MMPs and their cognate inhibitor TIMP-1.

Machine Enhanced Logic

AI evidence extraction

Structured fields below were generated from the paper’s abstract and metadata to make the evidence easier to inspect. Automated extraction may be incomplete or incorrect; verify important details against the original paper.

Study typein_vitro

Effect directionmixed

PopulationTHP-1 cells

Sample sizeNot supplied

ExposureELF · 0.05 MHz · 24 h

Evidence strengthLowConfidence: 74% · Peer reviewed: yes

Main findings

Outcomes measured

MMP activity and expression
TIMP-1 nitration (putative sites via molecular modeling)
Anti-oxidant enzyme activity
Nitrogen intermediates / iNOS pathway involvement

Limitations

In vitro cell model (THP-1) may not generalize to in vivo outcomes
Sample size not reported in abstract
Exposure limited to a single frequency (50 Hz), intensity (1 mT), and duration (24 h)
Mechanistic inference about TIMP-1 nitration relies in part on molecular modeling rather than direct confirmation (as described in abstract)

View raw extracted JSON

{
  "study_type": "in_vitro",
  "exposure": {
    "band": "ELF",
    "source": null,
    "frequency_mhz": 0.05,
    "sar_wkg": null,
    "duration": "24 h"
  },
  "population": "THP-1 cells",
  "sample_size": null,
  "outcomes": [
    "MMP activity and expression",
    "TIMP-1 nitration (putative sites via molecular modeling)",
    "Anti-oxidant enzyme activity",
    "Nitrogen intermediates / iNOS pathway involvement"
  ],
  "main_findings": "THP-1 cells exposed to a 50 Hz, 1 mT EMF for 24 h showed reduced anti-oxidant enzyme activity and increased nitrogen intermediates involving the iNOS pathway. The study examined whether nitration of TIMP-1 could contribute to increased MMP activity in EMF-exposed cells; molecular modeling identified plausible TIMP-1 tyrosine sites (Y120 and Y38 and/or Y72) for nitration.",
  "effect_direction": "mixed",
  "limitations": [
    "In vitro cell model (THP-1) may not generalize to in vivo outcomes",
    "Sample size not reported in abstract",
    "Exposure limited to a single frequency (50 Hz), intensity (1 mT), and duration (24 h)",
    "Mechanistic inference about TIMP-1 nitration relies in part on molecular modeling rather than direct confirmation (as described in abstract)"
  ],
  "evidence_strength": "low",
  "confidence": 0.74,
  "peer_reviewed_likely": "yes",
  "keywords": [
    "electromagnetic field",
    "ELF-EMF",
    "50 Hz",
    "1 mT",
    "THP-1",
    "matrix metalloproteinases",
    "MMP",
    "TIMP-1",
    "oxidative stress",
    "reactive nitrogen species",
    "iNOS",
    "nitration",
    "LPS"
  ],
  "suggested_hubs": [
    {
      "slug": "mechanisms-oxidative-stress",
      "weight": 0.78,
      "reason": "Reports reduced anti-oxidant enzyme activity and increased nitrogen intermediates/iNOS pathway in EMF-exposed THP-1 cells."
    }
  ]
}

AI can be wrong. Always verify against the paper.

AI-extracted fields are generated from the abstract and metadata and may be incomplete or incorrect. This material is for informational purposes and is not medical advice.

Identifiers and source

DOI: 10.1002/jcp.23024
PubMed: 21928345

Read the original paper →

Related papers

← Back to the Research Library