The relationship between serum prolidase activity and histone H3 protein levels and fibromyalgia 2022 Ozturk et al

OBJECTIVE: Fibromyalgia (FM) is a clinical syndrome characterized by prominent physical and psychological impairment and widespread pain on both sides of the body, above and below the waist, and along the axial skeleton. It often causes sleep difficulties, memory impairment, mood changes, irritable bowel syndrome, and fatigue. Our study aimed to investigate the relationship between FM and prolidase (peptidase D) and histone H3 protein levels by comparing a patient group with a healthy control group.

PATIENTS AND METHODS: In total, 176 people were examined in our study, 88 of whom were healthy and 88 of whom had FM. Serum level was measured by ELISA. Then the results were analyzed using SPSS. All p < 0.05 were considered statistically significant.

RESULTS: A significant increase in the levels of prolidase was observed in the patient group compared with the control group (6.28-4.68, p <0.001). Histone H3 protein values were not significantly different between the patient and control groups (p=0.184). The ROC analysis indicated that prolidase was statistically significant in disease prediction (p<0.001, AUC: 0.795 (0.697-0.893), while histone H3 protein was statistically insignificant in predicting disease.

CONCLUSIONS: The results of the study show that prolidase activity may play a role in diagnosing FM. In addition, since no study like ours has been performed before, it can bring a new perspective to the literature.

Open access, https://www.europeanreview.org/article/30659

 

This seems quite significant:

"Conclusions

The serum levels of prolidase were elevated in patients with FM compared with the control group. However, histone H3 levels did not differ between the patient and control groups. According to the ROC analysis, prolidase was statistically significant in the prediction of disease, while histone H3 was not. Although more studies are required, it is thought that prolidase can be used as a biomarker in the diagnosis of FM."

Prolidase is vital to a whole number of organic processes and the significance of high serum prolidase doesn't to be well established - a recent review covers the basics of what is known: PROLIDASE: A Review from Discovery to its Role in Health and Disease

"Abstract

Prolidase (peptidase D), encoded by the PEPD gene, is a ubiquitously expressed cytosolic metalloproteinase, the only enzyme capable of cleaving imidodipeptides containing C-terminal proline or hydroxyproline.

Prolidase catalyzes the rate-limiting step during collagen recycling and is essential in protein metabolism, collagen turnover, and matrix remodeling. Prolidase, therefore plays a crucial role in several physiological processes such as wound healing, inflammation, angiogenesis, cell proliferation, and carcinogenesis.

Accordingly, mutations leading to loss of prolidase catalytic activity result in prolidase deficiency a rare autosomal recessive metabolic disorder characterized by defective wound healing. In addition, alterations in prolidase enzyme activity have been documented in numerous pathological conditions, making prolidase a useful biochemical marker to measure disease severity. Furthermore, recent studies underscore the importance of a non-enzymatic role of prolidase in cell regulation and infectious disease.

This review aims to provide comprehensive information on prolidase, from its discovery to its role in health and disease, while addressing the current knowledge gaps."

Open access: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8438212/