Dynamic thiol and disulphide homoeostasis in fibromyalgia

Ameliorative effect of nano-pregabalin in gastrocnemius muscle of gamma irradiated rats with an experimental model of fibromyalgia: Crosstalk of Sirt3, IL-1β and PARP1 pathways

BACKGROUND

Fibromyalgia (FM) is a complex syndrome with somatic symptoms connected to the operational state of muscles. Although radiotherapy is a cornerstone in cancer treatment, it is implicated in the aggravation of FM. Lately, formulation of medicines in nano-forms become of great prominence due to their prospective applications in medicine. So, this study aimed to assess possible therapeutic benefits of formulating pregabalin in a nono-form (N-PG) for managing FM during exposure to gamma radiation.

METHODS

Gamma rays administered in fractionated doses (2 Gy/day) to male rats after one hour of s.c. injection of reserpine (1 mL/kg per day) to induce FM, then treated with single daily dose of (30 mg/kg, p.o.) PG or N-PG for ten successive days. Rats were subjected to behavioral tests, then sacrificed to obtain serum and gastrocnemius muscles.

RESULTS

N-PG significantly antagonized reserpine-induced FM as proved by; the immobility and performance times in forced swim and rotarod performance tests, respectively were restored near to the normal time, serum IL-8 and MCP-1 chemokines were nearby the normal levels, mitigated oxidative stress through increasing total thiol, Sirt3, CAT enzyme and decreasing COX-1, inhibition of inflammation via IL-1β and MIF significant reduction, it possessed anti-apoptotic effect verified by decreasing PARP-1 and increasing Bcl-XL, gastrocnemius muscles had minimal fibrosis levels as seen after Masson trichrome staining. Histopathological results were coincidence with biochemical inspection.

CONCLUSION

This study identifies N-PG as a novel drug that could be of a value in the management of FM particularly in cancer patients undergoing radiotherapy.

Skin Bioimpedance Analysis to Determine Cellular Integrity by Phase Angle in Women with Fibromyalgia: A Cross-Sectional Study

Oxidative stress has been proposed as a significant part of the pathogenesis of fibromyalgia, and the phase angle in bioelectrical impedance analysis has been explored as a potential technique to screen oxidative abnormalities. This study recruited 35 women with fibromyalgia and 35 healthy women, who underwent bioelectrical impedance analysis and maximum isometric handgrip strength tests. Women with fibromyalgia showed lower bilateral handgrip strength (right hand: 16.39 ± 5.87 vs. 27.53 ± 4.09, p < 0.001; left hand: 16.31 ± 5.51 vs. 27.61 ± 4.14, p < 0.001), as well as higher body fat mass (27.14 ± 10.21 vs. 19.94 ± 7.25, p = 0.002), body fat percentage (37.80 ± 8.32 vs. 30.63 ± 7.77, p < 0.001), and visceral fat area (136.76 ± 55.31 vs. 91.65 ± 42.04, p < 0.01) compared with healthy women. There was no statistically significant difference in muscle mass between groups, but women with fibromyalgia showed lower phase angles in all body regions when compared with healthy control women (right arm: 4.42 ± 0.51 vs. 4.97 ± 0.48, p < 0.01; left arm: 4.23 ± 0.48 vs. 4.78 ± 0.50, p < 0.001; trunk: 5.62 ± 0.77 vs. 6.78 ± 0.84, p < 0.001; right leg: 5.28 ± 0.56 vs. 5.81 ± 0.60, p < 0.001; left leg: 5.07 ± 0.51 vs. 5.69 ± 0.58, p < 0.001; whole body: 4.81 ± 0.47 vs. 5.39 ± 0.49, p < 0.001). Moreover, whole-body phase-angle reduction was only predicted by the presence of fibromyalgia (R2 = 0.264; β = 0.639; F(1,68) = 24.411; p < 0.001). Our study revealed significantly lower phase angle values, lower handgrip strength, and higher fat levels in women with fibromyalgia compared to healthy controls, which are data of clinical relevance when dealing with such patients.

Oxidative stress may be a contributing factor in fibromyalgia patients' pain mechanisms

OBJECTIVE

The pathophysiology of fibromyalgia (FM), a continuously painful syndrome with no known origin, has been related to mitochondrial dysfunction, oxidative stress, and inflammation. Recent studies have shown that FM may be associated with an oxidative balance disorder. The objective of this study was to measure the levels of oxidative stress in FM patients and try to understand the association between FM and free radicals.

METHODS

This study was performed on 100 volunteers admitted to the University of Health Sciences, Sultan 2, Abdulhamid Han Health Application and Research Center Physical Therapy and Rehabilitation Clinic, including 50 healthy controls and 50 patients with FM. To analyze oxidative stress biomarkers, total oxidant status (TOS) and total antioxidant status (TAS) levels were measured. Total thiol (TT) and native thiol (NT) concentrations were measured to determine the relationship between thiol groups. Disulfide (DIS) and oxidative stress index (OSI) were calculated with mathematical formulas.

RESULTS

While TOS and OSI levels were statistically higher in FM patients, TAS levels were significantly lower compared to the healthy control group (p<0.001). In comparison to the healthy control group, FM patients had considerably decreased TT and NT levels. DIS levels were significantly higher in FM patients than in controls (p<0.001).

CONCLUSIONS

Reactive oxygen species have several negative impacts on the human body. As a result of the measurements we analyzed, the relationship between FM and oxidative stress should be studied in terms of disease progression and may help improve the treatment process.

Changes in Dynamic Thiol/Disulfide Homeostasis, and Substance P, B-Endorphin and α-Tocopherol Concentrations in the Spinal Cord of Chronically Lame Dairy Cows

Initial lameness inflammation leads to chronic lameness and development of chronic pain due to the release of pro-inflammatory mediators such as reactive oxygen species (ROS), which are implicated in the transition from acute to chronic pain, and free radical scavengers countering thiol, substance P (SP), and β-endorphin (BE). The present study aimed to evaluate the dynamic thiol-disulfide homeostasis, α-tocopherol concentrations and SP and BE concentrations in the spinal cord of chronically lame dairy cows. Ten lame and 10 non-lame cows with a parity range of 2-6 were selected for the study. Lame cows had a history of up to 3 months of lameness. Spinal cord samples were obtained from the L2 to L4 lumbar vertebrae aspect of each animal. A thiol-disulfide homeostasis assay was performed using absorbance, and the α-tocopherol concentration was determined by HPLC. SP and BE concentrations were measured using ELISA kits. The results indicated that SP and BE were significantly higher in the spinal cord of lame cows. In contrast, disulfide levels and α-tocopherol concentrations were significantly lower in the spinal cord of lame cows. In conclusion, disulfide levels and α-tocopherol concentrations indicated a defective antioxidant response in cows with chronic lameness. The results of SP and BE concentrations suggested chronic pain and a defective endogenous analgesic response.

Thiol/disulfide homeostasis impaired in patients with primary Sjögren's syndrome

Background

Primary Sjögren's syndrome (pSS) is a disease associated with the overexpression of proinflammatory cytokines, and oxidative stress is one of the factors responsible for its etiopathogenesis. This study aimed to investigate the thiol/disulphide homeostasis in pSS patients.

Methods

The study included 68 pSS patients and 69 healthy controls. Thiol/disulphide homeostasis (total thiol, native thiol, and disulphide levels) was measured using the automatic spectrophotometric method developed by Erel and Neselioglu, and the results of the 2 groups were compared.

Results

The gender and age distributions of the pSS and control groups were similar (P = 0.988 and P = 0.065). Total thiol and native thiol levels were lower in the pSS group than in the control group (470.08 ± 33.65 µmol/L vs. 528.21 ± 44.99 µmol/L, P < 0.001, and 439.14 ± 30.67 µmol/L vs. 497.56 ± 46.70 µmol/L, P < 0.001, respectively). There were no differences in disulphide levels between groups [17.00 (range 0.70-217.0) µmol/L vs. 14.95 (range 2.10-40.10) µmol/L, P = 0.195].

Conclusions

It was concluded that the thiol/disulphide balance shifted towards disulphide in patients with pSS.