Xanthine Oxidase Inhibitory Activity of Paronychia argentea L.
Jalal Fandi, Reem Mohammad*, Hasna Alhaj Hussein, Habib Abboud
Faculty of Pharmacy, International University for Science and Technology (IUST),
Daraa-Highway, Ghabagheb, Syrian Arab Republic.
*Corresponding Author E-mail: reemmohammad1121@gmail.com
ABSTRACT:
Given the lack of synthetic xanthine oxidase inhibitors, the associated enzyme with several common diseases along with the side effects and adverse reactions of existing medications, it became necessary to explore herbal remedies as alternative treatment options. Paronychia argentea L. was selected for this study due to its traditional use in medicine throughout the Mediterranean region. The objective of the study was to evaluate the xanthine oxidase inhibitory activity of various extracts from Paronychia argentea L. and to compare these effects with allopurinol, a widely used xanthine oxidase inhibitor (XOI). Aerial parts of Paronychia argentea L. were collected in Hama, Syria. Extracts were prepared from the dried plant using ethanolic, aqueous-chloroform, and chloroform solvents. The xanthine oxidase inhibitory activity was assessed spectrophotometrically by measuring absorbance at 295nm, which correlates with uric acid concentrations. (IC50) concentrations that inhibit 50% of xanthine oxidase (XO) activity were adopted for comparison between extracts and allopurinol. Paronychia argentea L. showed xanthine oxidase inhibitory activity. The highest inhibitory activity was for aqueous-chloroform extract followed by ethanolic extract and chloroform extract respectively. The IC50 value for allopurinol was (2.973μg/ml), while it was (11.759μg/ml), (78.87μg/ml), and (376.06μg/ml) for aqueous-chloroform, ethanolic, and chloroform extracts respectively. Based on these results, Paronychia argentea L. has a considerable xanthine oxidase inhibitory activity, making it a potential source for future treatment of hyperuricemia, gout and related diseases, which is consistent with its traditional use in the Mediterranean region.
KEYWORDS: Paronychia argentea L., Xanthine Oxidase (XO), Xanthine Oxidase Inhibitor (XOI), Uric acid, Gout.
INTRODUCTION:
When consuming foods rich in purines, such as meat and fish, the enzyme xanthine oxidase (XO) metabolises the purines into the final metabolic product, uric acid. Xanthine oxidase can generate molecules known as reactive oxygen species (ROS), linking to various diseases, including atherosclerosis, metabolic disorders, and inflammatory diseases in general. It can also mediate diseases such as cancer and ageing1.
High concentrations of uric acid mediated by xanthine oxidase cause gout, a debilitating disease2, which is characterised by hyperuricemia and recurrent joint inflammation3. Hyperuricemia associated with gout leads to the deposition of monosodium urate (MSU) in joints, causing acute onset of arthritis and chronic joint injuries, in addition to the formation of renal calculus2. Gout affects a large segment of the population and its incidence has increased by 63.44% over the past 2 decades, with a corresponding increase of 51.12% in global years lived with disability4. In the future, hyperuricemia is expected become the second most prevalent metabolic disorder after type 2 diabetes, and already, and its incidence has dramatically increased globally over the past few decades due to lifestyle changes5. Therefore, controlling xanthine oxidase levels is a crucial target for preventing and treating diseases associated with oxidative stress3. Xanthine oxidase inhibitors (XOIs) prevent the metabolism of purines to uric acid1. Allopurinol is the most widely used synthetic xanthine oxidase inhibitor for the treatment of gout6. However, a significant drawback of allopurinol is that some individuals may experience allergic reactions which could cause a rash or more severe complications, including liver function abnormalities, a potentially fatal complication known as "allopurinol hypersensitivity syndrome" and Toxic Epidermal Necrolysis syndrome (TENS)7. Generally, synthetic medications for gout can be effective in the short term, but they may lead to numerous side effects and adverse reactions over time, affecting various systems in the body. Furthermore, these medications do not prevent the progression of the disease, highlighting the urgent need for new therapeutic options1. Recently, there has been increased interest in the role of traditional herbal remedies in managing acute gout arthritis8. Antioxidants are among the most promising compounds for pharmaceutical applications, including alternative xanthine oxidase inhibitors that help lower uric acid levels2. The plants currently utilized for treating gout have been selected based on accumulated knowledge over thousands of years9. This study focuses on Paronychia argentea L., which belongs to the Caryophyllaceae family and is also known as Arabic tea10, widely recognized for its therapeutic applications in renal diseases, stomach ulcers, anorexia, prostate and bladder diseases. It has also been utilized in the treatment of kidney stones and heart ailments11. The medicinal properties of Paronychia argentea L. are well-documented in the existing literature12. This research aims to evaluate the xanthine oxidase (XO) inhibitory activity of Paronychia argentea L. to determine its potential as a herbal remedy for gout and other inflammatory-related diseases. Additionally, the study will compare the IC50 concentrations of Paronychia argentea L. with those of allopurinol to assess its viability as an alternative treatment.
MATERIALS AND METHODS:
Materials:
Chemicals:
Allopurinol, xanthine oxidase and xanthine were purchased from Sigma-Aldrich Chemicals (USA). Dimethylsulphoxide (DMSO), hydrochloric acid (HCl), methanol and other reagents of analytical grade were purchased from Merck (Germany).
Plant material:
Aerial parts of Paronychia argentea L. were collected from the Masyaf Mountains in Hama, Syria, during April and May 2023. The plant materials were identified and authenticated by the Faculty of Agriculture at Damascus University, Syria. They were air-dried at room temperature in a shaded area, away from humidity, then ground and sieved to obtain a powder with a diameter of 250μm. The powder was stored at room temperature, protected from light and moisture.
Preparation of extracts:
The extracts were obtained by following the method mentioned by Arkoub-Hamitouce and his colleagues13. 1g of the powder was taken and macerated at room temperature for 24hours in 4 ml of ethanol under shaking. Then, the suspension was poured and centrifuged at 3000g for 10min, evaporated under reduced pressure using rotary evaporation at 40°C until dryness. Then, the ethanolic, chloroform, and aqueous-chloroform (3:1, v/v) extracts were obtained by splitting the ethanolic extract, adding the assistant solvent and stirring the mixture for 2min. Opaque containers were used to protect the extracts from light at 5°C until use.
Effect of Paronychia argentea L. extracts on xanthine oxidase activity:
A spectrophotometer at 295nm was used to measure the inhibitory effect on XO under aerobic conditions. Allopurinol, the widely clinically used XOI, was the positive control for the inhibition test at different concentrations (10-100μg/ml). The reaction mixture contained the sample solution diluted in distilled water or DMSO in different concentrations (10 -100)μl, 300μl of 50mM sodium phosphate buffer (pH 7.5), 100μl of freshly prepared solution of the enzyme (0.2 units/ml of xanthine oxidase diluted in phosphate buffer) and 100μl of distilled water. The test mixture contents were pre-incubated at 37°C for 15min. After that, 200μl of substrate solution (0.15mM of xanthine) was added to the content. The reaction mixture was incubated at 37°C for 30 min. Then, the reaction was stopped by adding 200μl of 0.5M HCl. Next, UV/VIS spectrophotometer was used to measure the absorbance against the blank that contained the same ingredients except the enzyme solution which was replaced with the phosphate buffer. The control was prepared by having 100μl of DMSO instead of the test compounds that would give the maximum uric acid formation7. Evaluating the degree of XO inhibitory activity was determined using Eq.1, in which α is the activity of XO without the test sample and β is the activity of XO with the test sample14.
% XO inhibition = (1 – β/α) x 100 (1)
Statistical analysis:
All measurements were taken in triplicate. Mean values and standard deviations (mean±S.D.) were carried out using Microsoft Office Excel 2010, also used to assess the IC50 value using dose-response data of the logarithmic function curve.
Evaluation of the IC50 concentrations:
Various concentrations of allopurinol (10, 25, 50, 75, and 100μg/ml) as well as the sample extracts were evaluated for XO inhibitory activity. The dose-response logarithmic function curve was used to generate the equation determining the 50% inhibition7.
Table 1. XO inhibitory activity of three Paronychia argentea L. extracts in comparison with allopurinol
|
Concentration (μg/ml) |
XO inhibitory activity (%) a Ethanolic extract ±SD |
XO inhibitory activity (%) Chloroform extract ±SD |
XO inhibitory activity (%) Aqueous-chloroform extract (3:1, v/v) ±SD |
XO inhibitory activity (%) Positive control b ±SD |
|
100 |
55.68±3.4 |
42.2±1.24 |
84.85±2.1 |
92.81± 1.4 |
|
75 |
48.88±1.02 |
41.63±0.9 |
80.14±0.4 |
87.45±0.8 |
|
50 |
42.12±0.6 |
38.55±0.7 |
73.22±1.03 |
80.74±1.1 |
|
25 |
39.19±0.2 |
34.35±1.6 |
62.47±0.3 |
73.88±1.25 |
|
10 |
33.58±2.1 |
29.82±0.3 |
47.32±0.21 |
65.29±0.5 |
aXO inhibitory activity (%) depends on triplicate measurements. Results are expressed as means ± SD (n = 3).
bSynthetic XOI (Allopurinol) as a positive control.
RESULT AND DISCUSSION:
The XO inhibitory activity was measured for Paronychia argentea L. extracts at various concentrations. XO inhibitory activity percentages were placed in (Table 1), in comparison with allopurinol (positive control), the results showed the highest XOI activity was by aqueous-chloroform (3:1, v/v) extract 100ug/ml followed by ethanolic extract 100ug/ml and chloroform extract 100ug/ml. Overall, the inhibtion percentages support the possibility of obtaining an anti-gout supplement from Paronychia argentea L. as an alternative option to the allopurinol.
Inhibitory activity for each of allopurinol, aqueous-chloroform (3:1, v/v) extract, ethanolic extract, and chloroform extract of Paronychia argentea L. were also expressed in term of IC50, the concentration of positive control and samples extracts needed under experimental conditions to match 50% inhibition of XO. The IC50 value was calculated using dose-response logarithmic function curves as shown in (figure 1). Allopurinol had a lower IC50 value as compared to Paronychia argentea L. aqueous-chloroform (3:1, v/v) extract, ethanolic extract and chloroform extract (figure 2).
Figure 1. XO inhibitory activity (%) of allopurinol and three extracts of Paronychia argentea L.
y1 represents the dose-response logarithmic function curve of allopurinol.
y2 represents the dose-response logarithmic function curve of the aqueous-chloroform extract.
y3 represents the dose-response logarithmic function curve of the ethanolic extract.
y4 represents the dose-response logarithmic function curve of the chloroform extract.
Figure 2. Concentrations of Paronychia argentea L. extracts and allopurinol that inhibit 50% of XO activity (IC50)
Based on these results, allopurinol still has the best efficiency as a treatment of hyperuricemia, gout and other related-inflammatory diseases as compared to the studied extracts, but the difference in IC50 concentrations between it and the aqueous-chloroform (3:1, v/v) extract is acceptable and taking into consideration many side effects of allopurinol and limitations of available XOI drugs, a natural XOI will be better alternative option.
Paronychia argentea L. is rich in flavonoids which are responsible for most of the therapeutic effects shown in available literature12. Studies suggest that polyphenols and flavonoids presence in the extracts can be the reason for XO inhibition15. Derivatives of quercetina, jaceosidin and isorhamnetin are the major identified compounds in Paronychia argentea L.16. The difference in inhibitory activity can be attributed to different concentrations of polyphenols and flavonoids associated with solvent polarity17. Therefore, the proven XO inhibitory activity of Paronychia argentea L. probably is due to compounds that interact with the same site. However, more efforts are still needed to identify the compounds responsible for the activity, isolate them, improve extraction methods, and evaluate their efficiency.
CONCLUSION:
Paronychia argentea L. extracts were shown to be effective inhibitors of xanthine oxidase, which is suggested to be relevant to the significant content of flavonoids and polyphenols. The study indicates that this plant could be a rich source of compounds used in the treatment of hyperuricemia, gout, and other diseases associated with xanthine oxidase. Further research is recommended to isolate the active compounds from this plant and study their therapeutic activities in vivo and even clinically.
CONFLICT OF INTEREST:
The authors have no conflicts of interest regarding this investigation.
ACKNOWLEDGMENTS:
The authors would like to thank Al-Attar Company for allowing to utilise their laboratories.
REFERENCES:
1. Subba B. Kharel P. Rai, G. B. Studies on Antioxidant and Xanthine Oxidase Inhibitory Activities of Coccinia grandis (L.) Voigt, Datura metel (Linn.) and Tagetes patula (L.) from Rupandehi District of Nepal. Research Journal of Pharmacy and Technology. 2024; 17(10): 4765-4770. DOI:10.52711/0974-360X.2024.00734
2. Irawan C. Rochaeni H. Pradipta A. R. et al. Total Phenolic content and Potential of Black Betel Leaf (Piper betle L. var Nigra) Extract as an Antioxidant and Anti-Gout. Research Journal of Pharmacy and Technology. 2024; 17(3): 1128-1134. DOI: 10.52711/0974-360X.2024.00176
3. Manjuladevi K. Krishnan R. S. Rahini, P. A Review on Gouty Arthritis. Research Journal of Pharmacy and Technology. 2019; 12(11): 5583-5588. DOI:10.5958/0974-360X.2019.00967.3
4. He Q. Mok T. N. Sin T. H. et alGlobal, regional, and national prevalence of gout from 1990 to 2019: age-period-cohort analysis with future burden prediction. JMIR Public Health and Surveillance. 2023; 9(1): e45943. doi: 10.2196/45943
5. Mehmood A. Ishaq M. Zhao L. et al. Natural compounds with xanthine oxidase inhibitory activity: A review. Chemical Biology and Drug Design. 2019; 93(4): 384-418. doi: 10.1111/cbdd.13437
6. Pacher P. Nivorozhkin A. Szabó C. Therapeutic effects of xanthine oxidase inhibitors: renaissance half a century after the discovery of allopurinol. Pharmacological Reviews. 2006; 58(1): 87-114. DOI: https://doi.org/10.1124/pr.58.1.6
7. Azmi S. Jamal P. Amid A. Xanthine oxidase inhibitory activity from potential Malaysian medicinal plant as remedies for gout. International Food Research Journal. 2012; 19(1): 159-165
8. Irawan C. Khodijah E. Nurhayati L. et al. Optimization of ultrasound-assisted extraction in limau peels (Citrus amblycarpa), antioxidant activity and its potential as an inhibitor for xanthine oxidase. Research Journal of Pharmacy and Technology. 2023; 16(2): 750-758. DOI : 10.52711/0974-360X.2023.00128
9. Mechraoui O. Imessaoudene A. Maiz M. Y. et al. In vitro Antiurolithiatic activity of the leaves and flowers extracts of Paronychia argentea, a plant used in traditional medicine in Algeria. Indianjournals.com. 2021; 14 (6): 401-411. doi.org/10.52711/0974-4150.2021.00069
10. Corp N. Pendry B. The role of Western herbal medicine in the treatment of gout. Journal of Herbal Medicine. 2013; 3(4): 157-170. doi.org/10.1016/j.hermed.2013.08.002
11. Sait S. Hamri-Zeghichi S. Boulekbache-Makhlouf L. et al. HPLC-UV/DAD and ESI-MSn analysis of flavonoids and antioxidant activity of an Algerian medicinal plant: Paronychia argentea Lam. Journal of Pharmaceutical and Biomedical Analysis. 2015; 111: 231–240. //dx.doi.org/doi:10.1016/j.jpba.2015.03.027
12. Veeraraghavan V. P. Hussain S. Balakrishna J. P et al. Paronychia argentea: A critical comprehensive review on its diverse medicinal potential and future as therapeutics. Pharmacognosy Journal. 2020; 12(5): 1172-1179. DOI : 10.5530/pj.2020.12.165
13. Arkoub-Hamitouche L. González-del-Campo V. López-Oliva M. et al. Paronychia argentea Lam. protects renal endothelial cells against oxidative injury. Journal of Ethnopharmacology. 2020; 248: 112314. //doi.org/10.1016/j.jep.2019.112314
14. Naseem Saud A. Muhammad F. Muzammil Hasan N. et al. Activity of polyphenolic plant extracts as scavengers of free radicals and inhibitors of xanthine oxidase. Journal of Basic and Applied Sciences. 2006; 2(1): 1-6. ID: emr-77715
15. Abdullahi A. Hamzah R. Jigam A. et al. Inhibitory activity of xanthine oxidase by fractions Crateva adansonii. Journal of Acute Disease. 2012; 1(2): 126–129. doi.org/10.1016/S2221-6189(13)60029-3
16. Sait S. Hamri-Zeghichi S. Boulekbache-Makhlouf L. et al. HPLC-UV/DAD and ESI-MSn analysis of flavonoids and antioxidant activity of an Algerian medicinal plant: Paronychia argentea Lam. Journal of Pharmaceutical and Biomedical Analysis, 2015; 111: 231-240. doi.org/10.1016/j.jpba.2015.03.027
17. Enroth C. Eger B. T. Okamoto K. et al. Crystal structures of bovine milk xanthine dehydrogenase and xanthine oxidase: structure-based mechanism of conversion. Proceedings of the National Academy of Sciences. 2000; 97(20): 10723–10728. doi.org/10.1073/pnas.97.20.10723.
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Received on 02.12.2024 Revised on 01.04.2025 Accepted on 04.06.2025 Published on 02.08.2025 Available online from August 08, 2025 Research J. Pharmacy and Technology. 2025;18(8):3711-3714. DOI: 10.52711/0974-360X.2025.00534 © RJPT All right reserved
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