GC-MS-Based Assessment of Thyme Extract in Rheumatoid Arthritis Inflammation

Researchers at Koya University (Koya, Iran) aimed to investigate and evaluate the anti-inflammatory effect of alcoholic extract of thyme in animal models of rheumatoid arthritis (RA), to assess its potential in reducing inflammation. Phenolic contents and other active compounds of thyme were analyzed by gas chromatography-mass spectrometry (GC-MS). A paper based on their work was published in Cellular and Molecular Biology (1).

One of the most common immune-mediated diseases, RA typically presents itself as synovial joint pain, swelling, and stiffness exhibited by sufferers (2). Cartilage and bone deterioration is a hallmark of RA; these conditions often lead to joint pain and physical weakness in affected patients (3). The pathophysiology of RA involves a complex network of immune cells and cytokines, which contribute to cartilage and bone damage increasing the proliferation of synoviocytes, cells which line the joint capsule that thicken as the disease progresses (4). The pathogenesis of RA is mainly driven by cytokines, particularly interleukin-6 and TNF-alpha, although there have been recent studies showing that other cytokines, particularly interleukin-1, interleukin-17, and interleukin-23, also play a critical role in RA pathogenesis (5).

Well documented for its anti-inflammatory properties primarily through its essential oil (TEO) and active compounds like thymol (6), studies have examined the effect of thyme (Thymusvulgaris) in the treatment of a variety of diseases (7), including those of the autoimmune variety (8). While thyme has been numbered among the most frequently used herbal remedies among RA patients, the specific anti-inflammatory effect of its extract in the context of RA has not been experimentally evaluated in either human clinical studies or animal models (9). This represented a clear gap in the literature regarding the use of extract thyme to deliver a broader range of bioactive compounds for evaluating anti-inflammatory effect in rheumatoid arthritis using animal model, the researcher’s noted (1).

In this study, 15 male adult albino rats were divided into three groups of five. The first group was the control group and was fed on basal diet. The second group was the RA group,where the rats were inoculated with 0.1 ml of Complete Freund’s Adjuvant (CFA), yet fed on basal diet. The third group was the treatment group, in which rats were inoculated with CFA along with the administration of thyme extract orally for 22 days. The researchers reported that treatment with thyme extract significantly reduced proinflammatory cytokines IL-1 (interleukin-1), IL-6 (interleukin-6) and TNF- α (tumor-necrosis factor-alpha). Anti-inflammatory IL-10 (interleukin-10) showed a significant increase in the thyme-treated group. CD4 T (cluster of differentiation-4) cell levels showed a significant difference, while sCD14 (soluble cluster of differentiation-14) levels were non-significant in the thyme group compared to the RA group. Inflammatory markers (C-reactive proteins) CRP, and anti-cyclic citrullinated peptide ( anti-CCP) antibodies were both significantly elevated in RA and significantly reduced by thyme treatment. Although body weight changes were statistically not considered to be significant statistically, they were visibly prominent. Paw edema was significantly decreased in the thyme-treated group. Matrix-metalloproteinase (MMP)-1 levels and neutrophil counts were both elevated in RA and significantly reduced following thyme extract treatment (1).

The researchers believe that their study demonstrates that thyme extract exerts significant anti-inflammatory effects in a rat model of rheumatoid arthritis, which may offer a promising natural therapeutic approach for managing rheumatoid arthritis and its associated inflammation. However, while multiple pro-inflammatory and anti-inflammatory markers were measured, histological analysis results of joint tissue were not performed, which could have provided more definitive evidence of structural improvement. Further studies, therefore, are believed necessary for determining the structural effect of thyme through histological evaluation and further validate the therapeutic potential of the plant (1).

References

1. Blbas, S. S. S.; Fatah, H. R.; Blbas, S. S. I.. Anti-Inflammatory Effect of Thyme on Rheumatoid Arthritis in Animal Model. Cell. Mol. Biol. 2025, 71 (7), 56-63. DOI: 10.14715/cmb/2025.71.7.8
2. Brown; P.; Pratt, A. G.; Hyrich, K. L. Therapeutic Advances in Rheumatoid Arthritis. BMJ 2024, 384, e070856. DOI: 10.1136/bmj-2022-070856
3. Wang, Y.; Chen, S.; Du, K. et al. Traditional Herbal Medicine: Therapeutic Potential in Rheumatoid Arthritis. J. Ethnopharmacol.2021, 279, 114368. DOI: 10.1016/j.jep.2021.114368
4. Rheumatoid arthritis. Wikipedia. https://en.wikipedia.org/wiki/Rheumatoid_arthritis (accessed 2025-07-30).
5. Kondo, N.; Kuroda, T.; Kobayashi, D. Cytokine Networks in the Pathogenesis of Rheumatoid Arthritis. Int. J. Mol. Sci.2021, 22 (20), 10922. DOI: 10.3390/ijms222010922
6. Pandur, E.; Micalizzi, G.; Mondello, L. et al. Antioxidant and Anti-Inflammatory Effects of Thyme (Thymus vulgaris L.) Essential Oils Prepared at Different Plant Phenophases on Pseudomonas aeruginosa LPS-Activated THP-1 Macrophages. Antioxidants 2022, 11 (7), 1330. DOI: 10.3390/antiox11071330
7. Soltan Dallal, M. M.; Siavashi, M.; Karimaei, S. et al. The Effect of Thyme Essential Oil and Endothelial Progenitor Stem Cells on Lipopolysaccharide-Induced Sepsis in C57BL/6 Mice. Biotechnol. Appl. Biochem. 2024, 71 (4), 835-848. DOI: 10.1002/bab.2580
8. Mahmoodi, M.; Sedghy, F.; Jafarzadeh, A. Effect of Treatment with Thyme Extract on Urinary Levels of Melatonin in an Experimental Autoimmune Encephalomyelitis Mouse Model. Rep. Biochem. Mol. Biol. 2020, 8 (4), 407-412. http://rbmb.net/article-1-388-en.html
9. Rambod, M.; Nazarinia, M.; Raieskarimian, F. The Prevalence and Predictors of Herbal Medicines Usage Among Adult Rheumatoid Arthritis Patients: A Case-Control Study. Complement. Ther. Med. 2018, 41, 220-224. DOI: 10.1016/j.ctim.2018.10.004