Phosphodiesterase 4D gene and risk of noncardiogenic ischemic stroke in a Korean population

Phosphodiesterase 4 inhibition as a novel treatment for stroke

The incidence of stroke ranks third among the leading causes of mortality worldwide. It has the characteristics of high morbidity, high disability rate and high recurrence rate. The current risk associated with stroke surgery is exceedingly high. It may potentially outweigh the benefits and fail to ameliorate the cerebral tissue damage following ischemia. Therefore, pharmacological intervention assumes paramount importance. The use of thrombolytic drugs is most common in the treatment of stroke; however, its efficacy is limited due to its time-sensitive nature and propensity for increased bleeding. Over the past few years, the treatment of stroke has witnessed a surge in interest towards neuroprotective drugs that possess the potential to enhance neurological function. The PDE4D gene has been demonstrated to have a positive correlation with the risk of ischemic stroke. Additionally, the utilization of phosphodiesterase 4 inhibitors can enhance synaptic plasticity within the neural circuitry, regulate cellular metabolism, and prevent secondary brain injury caused by impaired blood flow. These mechanisms collectively facilitate the recovery of functional neurons, thereby serving as potential therapeutic interventions. Therefore, the comprehensive investigation of phosphodiesterase 4 as an innovative pharmacological target for stroke injury provides valuable insights into the development of therapeutic interventions in stroke treatment. This review is intended for, but not limited to, pharmacological researchers, drug target researchers, neurologists, neuromedical researchers, and behavioral scientists.

Phosphodiesterase 4 D (PDE4D) gene polymorphisms and risk of ischemic stroke: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Studies on the relationship between Phosphodiesterase 4 D (PDE4D) gene polymorphism with the risk of ischemic stroke (IS) have shown discordant results. The present meta-analysis was aimed to clarify the relationship between PDE4D gene polymorphism with the risk of IS by estimating pooled analysis of published epidemiological studies.

METHODS

A comprehensive literature search for all the published articles was performed in various electronic databases, including PubMed, EMbase, Cochrane Library, Trip Database, Worldwide Science, CINAHL, and Google Scholar up to 22nd December 2021. Pooled Odds ratios (ORs) with 95% Confidence Intervals (CIs) under dominant, recessive, and allelic models were calculated. Subgroup analysis based on ethnicity (Caucasian vs. Asian) was performed to examine the reliability of these findings. Sensitivity analysis was also performed to detect the heterogeneity between studies. Finally, Begg's funnel plot was used to assess the potential for publication bias.

RESULTS

In our meta-analysis, we identified a total of 47 case-control studies with 20,644 ischemic stroke (IS) cases and 23,201 control subjects, including 17 studies of Caucasian descent and 30 studies of Asian descent. Our findings suggest that there was a significant relationship between SNP45 gene polymorphism and risk of IS (Recessive model: OR = 2.06, 95% CI 1.31-3.23), SNP83 overall (allelic model: OR = 1.22, 95% CI 1.04-1.42), Asian (allelic model: OR = 1.20, 95% CI 1.05-1.37), and SNP89 Asian (Dominant model: OR = 1.43, 95% CI 1.29-1.59, recessive model: OR = 1.42, 95% CI 1.28-1.58) respectively. However, no significant relationship was found between SNP32, SNP41, SNP26, SNP56, and SNP87 gene polymorphisms and risk of IS.

CONCLUSION

Findings of this meta-analysis conclude that SNP45, SNP83, and SNP89 polymorphism could be capable of increasing stroke susceptibility in Asians but not in the Caucasian population. Genotyping of SNP 45, 83, 89 polymorphisms may be used as a predictor for the occurrence of IS.

Association of plaque enhancement on vessel wall MRI and the phosphodiesterase 4D variant with stroke recurrence in patients with symptomatic intracranial atherosclerosis

PURPOSE

Vessel wall MRI (VW-MRI) can be used to evaluate the nature of intracranial atherosclerosis (ICAS) plaque in vivo. Phosphodiesterase 4D (PDE4D) participates in stroke development. This study aims to explore the value of VW-MRI findings and the PDE4D gene variant in predicting stroke recurrence in patients with ICAS.

METHODS

We prospectively recruited 324 symptomatic ICAS patients. VW-MRI was performed to determine luminal and wall changes. PDE4D gene single-nucleotide polymorphisms (SNPs)-namely, SNP32, SNP83, and SNP87-were determined by direct sequencing. The risk factors of stroke recurrence were analyzed using the multivariate Cox proportional hazards model.

RESULTS

Of the 324 subjects, 97 (29.9%) experienced recurrent ischemic stroke during the follow-up period. A total of 254 patients (78.4%) showed plaque enhancement; 87 of these patients experienced stroke recurrence. The CT/CC genotype frequencies of PDE4D83 were significantly higher in participants with recurrent stroke than in patients without stroke recurrence (p = 0.019 and p < 0.001, respectively). However, the PDE4D32 and PDE4D87 variants were not correlated with recurrent stroke. Multivariate analysis showed that plaque enhancement from VW-MRI (HR 4.52, 95% CI 2.35-8.73, p < 0.001) and the PDE4D83 variant (HR 7.43, 95% CI 1.75-31.87, p = 0.005) were independently correlated with stroke recurrence. Kaplan-Meier curves showed significant differences in stroke recurrence rates between the plaque-enhanced group and the non-enhanced group (p < 0.001) and between the PDE4D83 variant carriers and noncarriers (p = 0.002).

CONCLUSION

Plaque enhancement on VW-MRI and the presence of the PDE4D83 variant are associated with ischemic stroke recurrence in subjects with symptomatic ICAS.

A meta-analysis of PDE-gene polymorphism and cerebral infarction risk

Previous studies identified that phosphodiesterase 4D (PDE4D) gene polymorphism might be associated with cerebral infarction or ischemic stroke, and hemorrhagic stroke in human populations. However, as yet, no meta-analysis has revealed any detailed association. We retrospectively reviewed studies regarding the relationship of PDE4D gene polymorphism with ischemic stroke (IS) published during the period January 2003 to September 2012. According to the inclusion criteria, 9 of 105 initial studies were included in the subsequent analysis. The PubMed, Embase and CNKI of China were searched to identify the relevant studies. A total of 186 young patients with IS were included for the meta-analysis and 232 matched control subjects were enrolled and results were presented. The association of PDE4D gene polymorphism with IS in various populations was examined. The results suggested that single nucleotide polymorphism (SNP), SNP 83 in PDE4D gene was significantly related with susceptibility to IS. The meta-analysis also showed that PDE4D gene was associated with an enhanced risk of IS. The meta-analysis suggested that PDE4D SNP 87 constitutes an independent risk factor for IS development. To the best of our knowledge, the present meta-analysis reveals a number of possible associations between PDE4D gene polymorphism and IS.

Interleukin-6 Receptor Polymorphisms Contribute to the Neurological Status of Korean Patients with Ischemic Stroke

To investigate the contribution of the interleukin-6 receptor (IL-6R) gene single nucleotide polymorphisms (SNPs) to the neurological status of Korean patients with ischemic stroke (IS), two SNPs of the IL-6R gene (rs4845617, 5 UTR; rs2228144, Ala31Ala) were selected. IS patients were classified into clinical phenotypes according to two well-defined scores: the National Institutes of Health Stroke Survey (NIHSS) and the Modified Barthel Index scores. There were 121 IS patients and 291 control subjects. The SNP rs4845617 significantly contributed to the neurological status of patients with IS (P = 0.011 in codominant model 2, P = 0.006 in recessive model, and P = 0.008 in log-additive model). Allele frequencies of rs4845617 and rs2228144 demonstrated no significant difference in IS patients and controls. The AG and GG haplotypes differed between the NIHSS 1 (NIHSS scores < 6) group and the NIHSS 2 (NIHSS scores ≥ 6) group in patients with IS (P = 0.014, P = 0.0024). These results suggest that rs4845617 of the IL-6R gene is associated with the neurologic status of Korean patients with IS.

Assessment of two missense polymorphisms (rs4762 and rs699) of the angiotensinogen gene and stroke

The renin-angiotensin system has an important role in the pathogenesis of stroke. We investigated whether two missense single nucleotide polymorphisms (SNPs; rs4762, Thr207Met, T207M; and rs699, Met268Thr, M268T) of angiotensinogen (AGT; serpin peptidase inhibitor, clade A, member 8) are associated with the development and clinical phenotypes of ischemic stroke (IS) and intracerebral hemorrhage (ICH). We analyzed 197 stroke patients (120 IS and 77 ICH) and 301 control subjects. The patients were classified into subgroups in accordance to the scores of the National Institutes of Health Stroke Survey (NIHSS, <6 and ≥6) and Modified Barthel Index (MBI, <60 and ≥60). Multiple logistic regression models were used to analyze the genotype and allele distributions of each SNP. One of the missense SNPs, rs4762 (T207M) was associated with the development of ICH (P=0.038 in log-additive model and P=0.021 in allele distributions). The T allele frequency of T207M was higher in the ICH group (16.2%) compared with the control group (9.6%). The TC haplotype frequency differed significantly between the ICH and control groups (P=0.014). With regard to clinical features, T207M correlated with the NIHSS scores of the ICH patients (P=0.039 in codominant1, P=0.015 in dominant, P=0.011 in overdominant and P=0.039 in log-additive models). However, the two missense SNPs, rs4762 and rs699, were not associated with IS and its clinical features, including NIHSS and MBI scores. These data suggest that a missense SNP (rs4762, T207M) of the AGT gene may be associated with the development of ICH and contribute to the neurological functional levels of ICH patients.

Genetic variation in phosphodiesterase (PDE) 7B in chronic lymphocytic leukemia: overview of genetic variants of cyclic nucleotide PDEs in human disease

Expression of cyclic adenosine monophosphate-specific phosphodiesterase 7B (PDE7B) mRNA is increased in patients with chronic lymphocytic leukemia (CLL), thus suggesting that variation may occur in the PDE7B gene in CLL. As genetic variation in other PDE family members has been shown to associate with numerous clinical disorders (reviewed in this manuscript), we sought to identify single-nucleotide polymorphisms (SNPs) in the PDE7B gene promoter and coding region of 93 control subjects and 154 CLL patients. We found that the PDE7B gene has a 5' non-coding region SNP -347C>T that occurs with similar frequency in CLL patients (1.9%) and controls (2.7%). Tested in vitro, -347C>T has less promoter activity than a wild-type construct. The low frequency of this 5' untranslated region variant indicates that it does not explain the higher PDE7B expression in patients with CLL but it has the potential to influence other settings that involve a role for PDE7B.

Sex-differential genetic effect of phosphodiesterase 4D (PDE4D) on carotid atherosclerosis

BACKGROUND

The phosphodiesterase 4D (PDE4D) gene was reported as a susceptibility gene to stroke. The genetic effect might be attributed to its role in modulating the atherogenic process in the carotid arteries. Using carotid intima-media thickness (IMT) and plaque index as phenotypes, the present study sought to determine the influence of this gene on subclinical atherosclerosis.

METHODS

Carotid ultrasonography was performed on 1013 stroke-free subjects who participated in the health screening programs (age 52.6 +/- 12.2; 47.6% men). Genotype distribution was compared among the high-risk (plaque index > or = 4), low-risk (index = 1-3), and reference (index = 0) groups. We analyzed continuous IMT data and further dichotomized IMT data using mean plus one standard deviation as the cutoff level. Because the plaque prevalence and IMT values displayed a notable difference between men and women, we carried out sex-specific analyses in addition to analyzing the overall data. Rs702553 at the PDE4D gene was selected because it conferred a risk for young stroke in our previous report. Previous young stroke data (190 cases and 211 controls) with an additional 532 control subjects without ultrasonic data were shown as a cross-validation for the genetic effect.

RESULTS

In the overall analyses, the rare homozygote of rs702553 led to an OR of 3.1 (p = 0.034) for a plaque index > or = 4. When subjects were stratified by sex, the genetic effect was only evident in men but not in women. Comparing male subjects with plaque index > or = 4 and those with plaque index = 0, the TT genotype was over-represented (27.6% vs. 13.4%, p = 0.008). For dichotomized IMT data in men, the TT genotype had an OR of 2.1 (p = 0.032) for a thicker IMT at the common carotid artery compared with the (AA + AT) genotypes. In women, neither IMT nor plaque index was associated with rs702553. Similarly, SNP rs702553 was only significant in young stroke men (OR = 1.8, p = 0.025) but not in women (p = 0.27).

CONCLUSIONS

The present study demonstrates a sex-differential effect of PDE4D on IMT, plaque index and stroke, which highlights its influence on various aspects of atherogenesis.