Long-Term Safety and Effectiveness of Diquafosol for the Treatment of Dry Eye in a Real-World Setting: A Prospective Observational Study

A Possible Reciprocal Relationship Between Myopia and Dry Eye Disease in Japanese Teenagers

Purpose

To investigate the relationship between dry eye disease (DED) and myopia in Japanese teenagers.

Methods

This clinic-based, retrospective, cross-sectional study assessed DED condition in 10- to 19-year-old teenagers presenting at Japanese eye clinics. They included 106 high myopic patients (HM; mean age, 16.4 ± 2.2 years), 494 mild myopic patients (15.0 ± 2.6 years) and 82 non-myopic teenagers (NM; 13.8 ± 2.6 years). Subjective refraction and anisometropia were measured. Myopia grade was classified as HM (≤ -6.00 D), MM (> -6.00 D, < -0.50 D), or NM (≥ -0.5 D). The presence of DED-related symptoms including dryness, irritation, pain, fatigue, blurring and photophobia were assessed through a questionnaire. Tear film break-up time (BUT) and fluorescein corneal staining were investigated. Comparison among three groups and regression analysis of myopic error and other variables were conducted.

Results

Anisometropia and astigmatic error were greatest in the HM group compared with the other groups (p < 0.001). The HM group reported less photophobia (p < 0.001) and less pain (p = 0.039) compared with the NM group. Regression analysis revealed that myopic error was correlated with astigmatic error (β = -0.231, p <0.001), anisometropia (β = -0.191, p <0.001), short BUT (β = -0.086, p = 0.028) and the presence of diagnosed DED (β = -0.112, p = 0.003). Dryness (β = -0.127 p = 0.004), photophobia (β = 0.117, p = 0.002) and pain (β = 0.084, p = 0.034) correlated with myopic error.

Conclusion

This study associated clinical findings of DED in HM teenagers. The present results suggest DED might be associated with myopia, possibly in a reciprocal relationship.

How does ocular graft-versus-host disease fit under the dry eye umbrella? A review

Graft-versus-host disease (GVHD) is a systemic disease that can affect multiple organs as a consequence of an allogeneic haematopoietic stem cell transplant. One organ system that is often affected in GVHD is the eyes. Ocular GVHD (oGVHD) may involve various structures within the eye including the lacrimal glands, eyelids, conjunctiva, cornea, and nasolacrimal ducts, and is a source of morbidity in patients with GVHD. Common presenting features of GVHD overlap with dry eye disease (DED), including decreased tear production, epithelial disruption, and Meibomian gland dysfunction (MGD). In this review, we aim to compare oGVHD and DED to better understand the similarities and differences between the conditions, with a focus on pathophysiology, risk factors, clinical features, and treatments.

Effects of diquafosol sodium in povidone iodine-induced dry eye model

AIM

To investigate the effects of diquafosol sodium (DQS) for dry eye model induced with povidone-iodine (PI) solution.

METHODS

Ten Sprague Dawley rats as the control group. Thirty Sprague Dawley rats were used to establish the dry eye model with stimulation of 10 g/L PI for 14d, then divided rats into three groups: dry eye group with no treatment (DED group, n=10); phosphate buffer saline treated group (PBS group, n=10); diquafosol treated group (DQS group, n=10). Clinical changes were observed by tear production test, fluorescein staining, tear break-up time (TBUT) test, corneal confocal microscope and ocular surface comprehensive analyzer. Eyeballs were collected on day 10 of treatment for hematoxylin-eosin (HE), periodic acid-Schiff (PAS), and alcian blue staining. TUNEL assay, polymorphonuclear (PMN) and mucin 1 (MUC1) immunofluorescence were performed and corneal ultrastructural changes were detected by electron microscopy.

RESULTS

Compared with DED and PBS groups, tear production (7.26±0.440 vs 4.07±0.474 mm; 7.26±0.440 vs 3.74±0.280 mm; all P<0.01) and TBUT (7.37±0.383s vs 1.49±0.260s; 7.37±0.383s vs 1.42±0.437s; all P<0.01) were significantly increased in DQS group. HE, PAS, and alcian blue staining and MUC1 immunofluorescence showed mucins and conjunctival goblet cells density (8.45±0.718 vs 5.21±0.813 cells/0.1 mm2; 8.45±0.718 vs 5.36±0.615 cells/0.1 mm2; all P<0.01) increased in DQS group. Confocal microscopy, PMN immunofluorescence and TUNEL staining showed inflammatory infiltration and corneal epithelial cells apoptosis decreased in DQS group. The increased number of microvilli in corneal epithelial and the recovered cell junction were observed in DQS group.

CONCLUSION

PI instillation can induce goblet cells and mucin loss, epithelial cell apoptosis and inflammation, which are consistent with the pathological manifestations of dry eye. Diquafosol can repair the ocular surface damage caused by PI, reduce corneal inflammation, inhibit corneal epithelial cell apoptosis, promote mucin secretion and maintain tear film stability.

Association of eye strain with dry eye and retinal thickness

PURPOSE

The purpose of this cohort study was to investigate the association between the prevalence of abnormal ocular examination results and the common visual symptoms of eye strain, blurred vision and photophobia.

METHODS

Consecutive first-visit outpatients with best-corrected visual acuity better than 20/30 in both eyes were enrolled and those with a history of intra-ocular lens implantation and glaucoma were excluded. Dry eye-related examinations and retinal thickness measurement were conducted. The odds ratio (OR) was calculated with logistic regression analyses of ocular data in relation to the presence of visual symptoms.

RESULTS

A total of 6078 patients (3920 women, mean age 49.0 ± 20.4 years) were analyzed. The prevalence of each symptom was 31.8% for eye strain, 22.5% for blurred vision and 16.0% for photophobia. A significant risk factor for eye strain was short tear break-up time (TBUT) (OR 1.88), superficial punctate keratitis (SPK) (OR 1.44), and thickness of ganglion cell complex (GCC) (OR 1.30). Risk factors for blurred vision were short TBUT (OR 1.85), SPK (OR 1.24) and GCC (OR 0.59). Risk factors for photophobia were short TBUT (OR 1.77) and SPK (OR 1.32). Schirmer test value, peripapillary nerve fiber layer thickness and full macular thickness were not associated with the tested symptoms.

CONCLUSION

The current study successfully identified female gender, short TBUT, and SPK as significant risk factors for eye strain, blurred vision, and photophobia with considerable ORs.

Protocol for a parallel assignment prospective, randomised, comparative trial to evaluate the safety and efficacy of intense pulsed light (IPL) combined with 3% diquafosol (DQS) ophthalmic solution in dry eye syndrome

INTRODUCTION

Evaporative dry eye (EDE) is common and can lead to ocular pain, decreased visual quality and reduced quality of life. Intense pulsed light (IPL) and 3% diquafosol ophthalmic solution have been found to be beneficial in reducing signs and symptoms of dry eye.

METHODS AND ANALYSIS

A randomised clinical trial will be performed at He Eye Specialist Hospital in Shenyang. 360 dry eye disease patients will be equally divided randomly into the IPL group, DQS group (3% diquafosol ophthalmic solution eye-drops) and IPL+group (IPL combined with 3% diquafosol eye-drops). All groups will be followed up for 4 weeks. The primary outcome measures will be the non-invasive tear break-up time and the Ocular Surface Disease Index change from the baseline. The secondary outcome measures willincludeconjunctival and cornea staining with fluorescein and lissamine, meibomian gland function and secretion quality, tear film lipid layer score, tear meniscus height, conjunctival hyperemia (redness score) changes . Adverse events also will be monitored and documented.

DISCUSSION

This study aimed to assess whether the combination of IPL with 3% diquafosol ophthalmic solution (study group), IPL+ (study group), is more effective than IPL (active control group) or DQS (active control group) in participants with EDE.

ETHICS AND DISSEMINATION

Management of dry eye with IPL combined with 3% diquafosol ophthalmic solution, registered on 23 January 2023. Ethics approval number: IRB (2022) K029.01. The study's findings will be shared regardless of the effect's direction.

TRIAL REGISTRATION NUMBER

NCT05694026.

Short-term application of diquafosol ophthalmic solution benefits children with dry eye wearing orthokeratology lens

Purpose

This aim of this study was to evaluate the effect of 3% Diquafosol Ophthalmic Solution (DQS) on children with dry eye from wearing overnight orthokeratology (OrthoK) lenses.

Methods

Myopic children aged 8-18 years with dry eye syndrome were enrolled in this prospective observational study, and they were grouped according to their OrthoK treatment history for at least 1 year. All participants received DQS 4 times per day for 1 month. The following indicators were measured at baseline 1 month after treatment: the Dry Eye Questionnaire-5 (DEQ-5), non-invasive tear meniscus height (TMH), non-invasive tear film break-up time (first and average, NIBUT-F and NIBUT-A), meibomian gland score (MG score), conjunctival hyperemia redness score (R-scan), and blink pattern analysis.

Results

A total of 104 participants (189 eyes) including 40 OrthoK wearers (72 eyes) and 64 Orthok candidates (117 eyes) completed the study. Of all, after DQS treatment for 1 month, DEQ-5 scores reduced from 5.54 ± 3.25 to 3.85 ± 2.98 (t = -3.36, p = 0.00). TMH increased from 0.20 ± 0.05 mm to 0.21 ± 0.05 mm (t = 2.59, p = 0.01), NIBUT-F and NIBUT-A were prolonged from 6.67 ± 4.71 s to 10.32 ± 6.19 s and from 8.86 ± 5.25 s to 13.30 ± 6.03 s (all p = 0.00), respectively. R-scan decreased from 0.69 ± 0.28 to 0.50 ± 0.25 (t = -9.01, p = 0.00). Upper MG scores decreased from 1.04 ± 0.32 to 0.97 ± 0.36 (t = -2.14, p = 0.03). Lower MG scores, partial blink rate, partial blinks, and total blinks did not change significantly. Both break-up time (BUT) and R-scan improved significantly after DQS treatment for 1 month (all p = 0.00) in OrthoK candidates and OrthoK wearers. Among the OrthoK wearers, TMH and dry eye symptoms increased significantly (all p = 0.00) but did not increase in OrthoK candidates (p > 0.05). There were no adverse events related to DQS.

Conclusion

Diquafosol Ophthalmic Solution was effective for children wearing overnight orthokeratology in relieving dry eye symptoms and improving ocular surface parameters, which may help improve children's OrthoK wearing tolerance and compliance.

Effectiveness and Adherence of Dry Eye Patients Who Switched from Short- to Long-Acting Diquafosol Ophthalmic Solution

Long-acting (lasting extend) diquafosol ophthalmic solution 3% (DQSLX) is administered three times daily versus six times daily for the currently approved diquafosol ophthalmic solution (DQS). We investigated the efficacy and adherence of switching from DQS to DQSLX in patients with dry eye disease. We retrospectively enrolled 54 patients (17 men and 37 women) with eye drop prescription changes from DQS to DQSLX between December 2022 and March 2023. The number of eye drops, subjective symptoms, tear breakup time (TBUT), and fluorescein staining scores from baseline to 4 weeks after starting DQSLX were evaluated. Participants then chose between DQSLX and DQS. Patients administered DQSLX three times per day, as listed on the package insert, 88.9% of the time; significantly higher than the 5.6% of patients who used DQS six times per day, as instructed. The DQSLX group showed significant improvements in symptoms and fluorescein staining scores (23.3 ± 20.1 and 0.8 ± 1.7, respectively) compared with the baseline (37.8 ± 24.1 and 1.1 ± 1.5, p = 0.01 and <0.001, respectively). The TBUT in the DQSLX group (5.0 ± 2.5 s) did not significantly improve compared to the DQS group (4.5 ± 1.7 s) (p = 0.75). Fifty-one (94.4%) patients opted to continue DQSLX because of the pleasant feeling of the eye drops, long-lasting moisture, and less frequent administration. The efficacy and adherence of DQSLX was comparable to DQS.

Improving ocular bioavailability of hydrophilic drugs through dynamic covalent complexation

The clinical benefits of diquafosol tetrasodium (DQS), a hydrophilic P2Y2 receptor agonist for dry eye, have been hindered by a demanding dosing regimen. Nevertheless, it is challenging to achieve sustained release of DQS with conventional drug delivery vehicles which are mainly designed for hydrophobic small molecule drugs. To address this, we developed an affinity hydrogel for DQS by taking advantage of borate-mediated dynamic covalent complexation between DQS and hydroxypropyl guar. The resultant formulation (3% DQS Gel) was characterized by sustained release, low corneal permeation, and extended ocular retention, which were desirable attributes for ocular surface drug delivery. Both in vitro and in vivo studies had been carried out to verify the biocompatibility of 3% DQS Gel. Using corneal fluorescein staining, the Schirmer's test, PAS staining, quantitative PCR and immunohistological analyses as outcome measures, the superior therapeutic effects of 3% DQS Gel over PBS, the hydrogel vehicle and free DQS were demonstrated in a mouse dry eye model. Our DQS delivery strategy reported herein is readily applicable to other hydrophilic small molecule drugs with cis-diol moieties, thus providing a general solution to improve clinical outcomes of numerous diseases.

Combination therapy with 3% diquafosol tetrasodium ophthalmic solution and sodium hyaluronate: an effective therapy for patients with dry eye after femtosecond laser-assisted in situ keratomileusis

Purpose

To assess the effect of combination therapy with 3% diquafosol tetrasodium (DQS) and sodium hyaluronate (HA) for dry eye after femtosecond laser-assisted in situ keratomileusis (FS-LASIK).

Design

Prospective nonrandomized comparative trial.

Methods

The prospective study included 80 eyes of 40 patients who underwent FS-LASIK with or without preoperative dry eye. Patients were divided into a combination group and a HA group according to their willingness and the doctor's advice. The combination group was treated with DQS six times a day and HA four times a day, and the HA group was treated with HA four times a day after FS-LASIK. Ocular surface disease index (OSDI), ocular symptom score, vision-related score, environmental score, tear meniscus height (TMH), first non-invasive tear breakup time (NIBUT-First), average non-invasive tear breakup time (NIBUT-Ave), tear breakup time (TBUT), Schirmer I test (SIT), corneal fluorescein staining score (CFS), bulbar redness score, limbal redness score, lipid layer grade (LLG), meiboscore, lid margin abnormality, corneal sensitivity, and corneal nerve parameters were examined before surgery and at 1 week and 1 month after surgery. Surface regularity index (SRI) was also examined before surgery and at 1 month postoperatively.

Results

OSDI score (p = 0.024) and vision-related score (p = 0.026) were significantly lower in the combination group than in the HA group at 1 month after FS-LASIK, especially in patients with preoperative dry eye symptoms. The increasements of CFS (p = 0.018), bulbar redness score (p = 0.021), and limbal redness score (p = 0.009) were significantly lower in the combination group than in the HA group at 1 week after FS-LASIK. But other ocular surface parameters showed no difference between both groups at 1 week and 1 month after FS-LASIK. LLG was significantly higher in the combination group than in the HA group at 1 week (p = 0.004) and 1 month (p < 0.001) after surgery, especially in patients with high meiboscore. Additional DQS significantly improved corneal sensitivity in patients without preoperative dry eye symptoms at 1 month after FS-LASIK (p = 0.041).

Conclusion

The combination therapy with DQS and HA significantly relieved subjective symptoms, improved ocular surface status, and had the potential to promote corneal nerve growth in patients after FS-LASIK.

The developmental journey of therapies targeting purine receptors: from basic science to clinical trials

Since the discovery of ATP as an extracellular signalling molecule in 1972, purinergic signalling, mediated by extracellular purines and pyrimidines has been identified in virtually all mammalian tissues and is implicated in regulating fundamental cellular processes. In recent years, there has been an increasing focus on the pathophysiology and potential therapeutic interventions based on purinergic signalling. A vast range of compounds targeting purine receptors are in clinical development, and many more are in preclinical studies, which highlights the fast growth in this research field. As a tribute to Professor Geoffrey Burnstock's legacy in purinergic signalling, we present here a brief review of compounds targeting purine receptors that are in different stages of clinical trials. The review highlights the 50-year journey from basic research on purinergic receptors to clinical applications of therapies targeting purine receptors.

Ocular Surface Ion Transport and Dry Eye Disease

Purpose of Review

To review the role of ocular surface epithelial (corneal and conjunctival) ion transporters in the pathogenesis and treatment of dry eye disease (DED).

Recent Findings

Currently, anti-inflammatory agents are the mainstay of DED treatment, though there are several agents in development that target ion transport proteins on the ocular surface, acting by pro-secretory or anti-absorptive mechanisms to increase the tear fluid Film volume. Activation or inhibition of selected ion transporters can alter tear fluid osmolality, driving water transport onto the ocular surface via osmosis. Several ion transporters have been proposed as potential therapeutic targets for DED, including the cystic fibrosis transmembrane conductance regulator (CFTR), calcium-activated chloride channels (CaCCs), and the epithelial sodium channel (ENaC).

Summary

Ocular surface epithelial cell ion transporters are promising targets for pro-secretory and anti-absorptive therapies of DED.

Prevalence of Comorbidity between Dry Eye and Allergic Conjunctivitis: A Systematic Review and Meta-Analysis

This systematic review aimed to determine the comorbid dry eye (DE) and allergic conjunctivitis (AC) prevalence. We searched PubMed and EMBASE for articles published until 22 March 2022, combining the terms “(dry eye OR keratoconjunctivitis sicca) AND allergic conjunctivitis.” Study-specific estimates (DE and AC incidence rates among patients with AC and DE, respectively) were combined using the one-group meta-analysis in a random-effects model. The initial search yielded 700 studies. Five articles reporting AC incidence among individuals with DE and six articles reporting DE incidence among individuals with AC were included in the qualitative synthesis. In these nine articles, the total sample size was 7254 patients. The DE incidence among individuals with AC was 0.9–97.5%; the AC incidence among individuals with DE was 6.2–38.0%. One-group meta-analysis using a random-effects model showed that 47.2% (95% confidence interval: 0.165–0.779; 320/1932 cases) of patients with AC had comorbid DE and 17.8% (95% confidence interval: 0.120–0.236; 793/4855 cases) of patients with DE had comorbid AC, as defined by each article. Complimentary screening and treatment for patients with DE and AC may improve long-term outcomes and prevent chronic ocular damage in highly susceptible populations.

Efficacy and Safety of the Long-Acting Diquafosol Ophthalmic Solution DE-089C in Patients with Dry Eye: A Randomized, Double-Masked, Placebo-Controlled Phase 3 Study

Introduction

DE-089C is a newly developed long-acting formulation of diquafosol ophthalmic solution with less frequent administration (three times daily) than the currently approved and clinically used diquafosol ophthalmic solution (six times daily), hereinafter referred to as DQS. DE-089C is desirable for achieving better patient adherence in clinical practice for dry eye therapy. The objective of this study was to confirm the efficacy and safety of DE-089C in patients with dry eye compared to placebo.

Methods

This randomized, multicenter, double-masked, placebo-controlled, parallel-group phase 3 study was conducted in Japan. Patients with aqueous-deficient dry eye satisfying Schirmer’s test I results ≤ 5 mm/5 min were included. A total of 337 patients with dry eye were randomized in an equal ratio to treatment with DE-089C or placebo ophthalmic solution, three times daily for 4 weeks. The primary endpoint for efficacy was change in fluorescein corneal staining score from baseline to week 4. The incidence of adverse drug reactions was investigated for safety evaluation.

Results

The background characteristics of patients in the two groups were similar. Primary endpoint of change in fluorescein corneal staining score at week 4 in the DE-089C group was significantly improved compared with the placebo group (least squares mean difference − 0.51, 95% CI − 0.754 to − 0.269, P < 0.0001). The secondary endpoint of the Lissamine green conjunctival staining score was also significantly improved in the DE-089C group compared to that in the placebo group, while other secondary endpoints were not achieved in this study. Commonly (incidence ≥ 1%) reported adverse drug reactions in the DE-089C group were eye irritation (3.6%) and eye discharge (1.8%) with mild severity, and the incidences of these two events were not higher than those in previous clinical studies on DQS.

Conclusion

The efficacy and safety of DE-089C administered three times daily at half the dosage of DQS in patients with dry eye were confirmed in this study.

Trial Registration

Japan Pharmaceutical Information Center ID, JapicCTI-205177.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12325-022-02194-2.

Ocular Surface Ion-Channels Are Closely Related to Dry Eye: Key Research Focus on Innovative Drugs for Dry Eye

Abundant ion-channels, including various perceptual receptors, chloride channels, purinergic receptor channels, and water channels that exist on the ocular surface, play an important role in the pathogenesis of dry eye. Channel-targeting activators or inhibitor compounds, which have shown positive effects in in vivo and in vitro experiments, have become the focus of the dry eye drug research and development, and individual compounds have been applied in clinical experimental treatment. This review summarized various types of ion-channels on the ocular surface related to dry eye, their basic functions, and spatial distribution, and discussed basic and clinical research results of various channel receptor regulatory compounds. Therefore, further elucidating the relationship between ion-channels and dry eye will warrant research of dry eye targeted drug therapy.

Neutrophils and neutrophil extracellular trap components: Emerging biomarkers and therapeutic targets for age-related eye diseases

Age-related eye diseases, including dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy, represent a major global health issue based on their increasing prevalence and disabling action. Unraveling the molecular mechanisms underlying these diseases will provide novel opportunities to reduce the burden of age-related eye diseases and improve eye health, contributing to sustainable development goals achievement. The impairment of neutrophil extracellular traps formation/degradation processes seems to be one of these mechanisms. These traps formed by a meshwork of DNA and neutrophil cytosolic granule proteins may exacerbate the inflammatory response promoting chronic inflammation, a pivotal cause of age-related diseases. In this review, we describe current findings that suggest the role of neutrophils and their traps in the pathogenesis of the above-mentioned age-related eye diseases. Furthermore, we discuss why these cells and their constituents could be biomarkers and therapeutic targets for dry eye, glaucoma, age-related macular degeneration, and diabetic retinopathy. We also examine the therapeutic potential of some neutrophil function modulators and provide several recommendations for future research in age-related eye diseases.

The Effect of Diquafosol Ophthalmic Solution on Clinical Parameters and Visual Function in Soft Contact Lens-Related Dry Eye

INTRODUCTION

This study evaluated the efficacy and safety of diquafosol ophthalmic solution (DQS) in soft contact lens (SCL)-related dry eye using artificial tear as a control.

METHODS

This study enrolled 26 patients with SCL-related dry eye. DQS and artificial tears (AT) were instilled into the right and left eyes, respectively, with their SCLs on. Dry eye examinations (including tear film breakup time, tear volume, and staining score) were performed and visual function (including contrast sensitivity) was also evaluated before (at baseline) and after treatment (at 4- and 8-week examinations). Subjective symptoms were assessed separately in each eye using a questionnaire on dry eye in contact lens wearers. The results were compared before and after treatment, and between the right eyes treated with DQS (the DQS eye) and the left eyes treated with AT (the AT eye) using the mixed effect model.

RESULTS

Corneal and conjunctival staining scores at 8-week examination were significantly lower than those at baseline in the DQS eye (p = 0.03; p < 0.001, respectively), but no significant changes were observed in the AT eye. Most subjective symptoms improved significantly in both the DQS and AT eyes. However, major subjective symptoms (dryness and blurry vision) improved significantly only in the DQS eye at 8-week examination. Contrast sensitivity at 8-week examination in the DQS eye improved significantly at 12 cycles/degree compared to baseline (p = 0.001) and was significantly better than that in the AT eye (p = 0.03). There were no adverse events related to DQS or AT.

CONCLUSIONS

DQS was effective and safe for SCL-related dry eye. DQS also improved contrast sensitivity.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR), Identification No. UMIN000024064.

Purinergic Signalling in Allogeneic Haematopoietic Stem Cell Transplantation and Graft-versus-Host Disease

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is a curative therapy for blood cancers and other haematological disorders. However, allo-HSCT leads to graft-versus-host disease (GVHD), a severe and often lethal immunological response, in the majority of transplant recipients. Current therapies for GVHD are limited and often reduce the effectiveness of allo-HSCT. Therefore, pro- and anti-inflammatory factors contributing to disease need to be explored in order to identify new treatment targets. Purinergic signalling plays important roles in haematopoiesis, inflammation and immunity, and recent evidence suggests that it can also affect haematopoietic stem cell transplantation and GVHD development. This review provides a detailed assessment of the emerging roles of purinergic receptors, most notably P2X7, P2Y2 and A2A receptors, and ectoenzymes, CD39 and CD73, in GVHD.

From purines to purinergic signalling: molecular functions and human diseases

Purines and their derivatives, most notably adenosine and ATP, are the key molecules controlling intracellular energy homoeostasis and nucleotide synthesis. Besides, these purines support, as chemical messengers, purinergic transmission throughout tissues and species. Purines act as endogenous ligands that bind to and activate plasmalemmal purinoceptors, which mediate extracellular communication referred to as "purinergic signalling". Purinergic signalling is cross-linked with other transmitter networks to coordinate numerous aspects of cell behaviour such as proliferation, differentiation, migration, apoptosis and other physiological processes critical for the proper function of organisms. Pathological deregulation of purinergic signalling contributes to various diseases including neurodegeneration, rheumatic immune diseases, inflammation, and cancer. Particularly, gout is one of the most prevalent purine-related disease caused by purine metabolism disorder and consequent hyperuricemia. Compelling evidence indicates that purinoceptors are potential therapeutic targets, with specific purinergic agonists and antagonists demonstrating prominent therapeutic potential. Furthermore, dietary and herbal interventions help to restore and balance purine metabolism, thus addressing the importance of a healthy lifestyle in the prevention and relief of human disorders. Profound understanding of molecular mechanisms of purinergic signalling provides new and exciting insights into the treatment of human diseases.