Cerebrovascular Effects of Sildenafil in Small Vessel Disease: The OxHARP Trial.

BACKGROUND: Vascular cognitive impairment due to cerebral small vessel disease is associated with cerebral pulsatility, white matter hypoperfusion, and reduced cerebrovascular reactivity (CVR), and is potentially improved by endothelium-targeted drugs such as cilostazol. Whether sildenafil, a phosphodiesterase-5 inhibitor, improves cerebrovascular dysfunction is unknown. METHODS: OxHARP trial (Oxford Haemodynamic Adaptation to Reduce Pulsatility) was a double-blind, randomized, placebo-controlled, 3-way crossover trial after nonembolic cerebrovascular events with mild-moderate white matter hyperintensities (WMH), the most prevalent manifestation of cerebral small vessel disease. The primary outcome assessed the superiority of 3 weeks of sildenafil 50 mg thrice daily versus placebo (mixed-effect linear models) on middle cerebral artery pulsatility, derived from peak systolic and end-diastolic velocities (transcranial ultrasound), with noninferiority to cilostazol 100 mg twice daily. Secondary end points included the following: cerebrovascular reactivity during inhalation of air, 4% and 6% CO2 on transcranial ultrasound (transcranial ultrasound-CVR); blood oxygen-level dependent-magnetic resonance imaging within WMH (CVR-WMH) and normal-appearing white matter (CVR-normal-appearing white matter); cerebral perfusion by arterial spin labeling (magnetic resonance imaging pseudocontinuous arterial spin labeling); and resistance by cerebrovascular conductance. Adverse effects were compared by Cochran Q. RESULTS: In 65/75 (87%) patients (median, 70 years;79% male) with valid primary outcome data, cerebral pulsatility was unchanged on sildenafil versus placebo (0.02, -0.01 to 0.05; P=0.18), or versus cilostazol (-0.01, -0.04 to 0.02; P=0.36), despite increased blood flow (∆ peak systolic velocity, 6.3 cm/s, 3.5-9.07; P<0.001; ∆ end-diastolic velocity, 1.98, 0.66-3.29; P=0.004). Secondary outcomes improved on sildenafil versus placebo for CVR-transcranial ultrasound (0.83 cm/s per mm Hg, 0.23-1.42; P=0.007), CVR-WMH (0.07, 0-0.14; P=0.043), CVR-normal-appearing white matter (0.06, 0.00-0.12; P=0.048), perfusion (WMH: 1.82 mL/100 g per minute, 0.5-3.15; P=0.008; and normal-appearing white matter, 2.12, 0.66-3.6; P=0.006) and cerebrovascular resistance (sildenafil-placebo: 0.08, 0.05-0.10; P=4.9×10-8; cilostazol-placebo, 0.06, 0.03-0.09; P=5.1×10-5). Both drugs increased headaches (P=1.1×10-4), while cilostazol increased moderate-severe diarrhea (P=0.013). CONCLUSIONS: Sildenafil did not reduce pulsatility but increased cerebrovascular reactivity and perfusion. Sildenafil merits further study to determine whether it prevents the clinical sequelae of small vessel disease. REGISTRATION: URL: https://www.clinicaltrials.gov/study/NCT03855332; Unique identifier: NCT03855332.

The effect of cilostazol on late outcomes after endovascular treatment for occlusive femoropopliteal disease.

OBJECTIVE: Restenosis and late occlusion remain a significant problem for endovascular treatment of peripheral artery disease. This meta-analysis aims to evaluate the effect of cilostazol on late outcomes after endovascular repair of occlusive femoropopliteal disease. METHODS: A systematic literature review was conducted conforming to established criteria to identify articles published up to September 2023 evaluating late outcomes after endovascular treatment for atherosclerotic femoropopliteal disease. Eligible studies should compare outcomes between patients treated with cilostazol and patients not treated with cilostazol. Both prospective and retrospective studies were eligible. Late outcomes included primary patency (PP), restenosis, target lesion revascularization (TLR), and major amputation during follow-up. RESULTS: Overall, 10 clinical studies were identified for analysis including 4721 patients (1831 with cilostazol vs 2890 without cilostazol) that were treated for 5703 lesions (2235 with cilostazol vs 3468 without cilostazol). All studies were performed in Japan. Mean follow-up was 24.1 ± 12.5 months. Cilostazol was associated with a lower risk for restenosis (pooled odds ratio [OR], 0.503; 95% confidence interval [CI], 0.383-0.660; P < .0001). However, no association was found between cilostazol and TLR (pooled OR, 0.918; 95% CI, 0.300-2.812; P = .881) as well as major amputation (pooled OR, 1.512; 95% CI, 0.734-3.116; P = .263). Regarding primary patency, cilostazol was associated with a higher 12-month PP (OR, 3.047; 95% CI, 1.168-7.946; P = .023), and a higher 36-month PP (OR, 1.616; 95% CI, 1.412-1.850; P < .0001). No association was found between cilostazol and mortality during follow-up (pooled OR, .755; 95% CI, 0.293-1.946; P = .561). CONCLUSIONS: Cilostazol seems to have a positive effect on 1- to 3-year PP and restenosis rates among patients treated endovascularly for atherosclerotic femoropopliteal disease. A positive effect on TLR and amputation risk was not verified in this review.

Combining dipyridamole and cilostazol with up-dosing antihistamines improves outcomes in chronic spontaneous urticaria with high D-dimer levels: A randomized controlled trial.

In a double-blind, randomized controlled trial, we investigated the effectiveness of adding antiplatelet drugs to up-dosing antihistamines for the treatment of chronic spontaneous urticaria (CSU) in patients with elevated D-dimer levels who had an inadequate response to conventional antihistamine doses. Twenty patients with Urticaria Activity Score over 7 days (UAS7) ≥16 and D-dimer >500 ng/mL were randomized to receive either antiplatelet therapy (cilostazol 150 mg/day + dipyridamole 50 mg/day) with antihistamine (desloratadine 20 mg/day) or antihistamine alone for 4 weeks. The antiplatelet group demonstrated a greater decrease in UAS7 compared to the control group (28.10 to 8.90 vs. 22.90 to 16.40, p < 0.001 vs. p = 0.054). Both groups experienced improved quality of life (DLQI), but the improvement was greater in the antiplatelet group (p = 0.046). D-dimer levels decreased only in the antiplatelet group (1133.67 ng/mL to 581.89 ng/mL, p = 0.013) with no significant change observed in the control group. This suggests that combining dipyridamole and cilostazol with up-dosing antihistamines may be more effective for CSU patients with high D-dimer levels compared to up-dosing antihistamines alone. This could be due to a reduction in platelet activation, as evidenced by the decrease in D-dimer levels observed in the antiplatelet group.

Effect of cilostazol on healing of achilles tendon ruptures: an experimental study on rats.

PURPOSE: This study aimed to evaluate whether cilostazol (phosphodiesterase III inhibitor) could enhance the healing of Achilles tendon ruptures in rats. MATERIALS AND METHODS: The Achilles tendons of 24 healthy male adult rats were incised and repaired. The rats were randomly allocated to cilostazol and control groups. The cilostazol group received daily intragastric administration of 50 mg/kg cilostazol for 28 days, while the control group did not receive any medication. The rats were sacrificed on the 30th day, and the Achilles tendon was evaluated for biomechanical properties, histopathological characteristics, and immunohistochemical analysis. RESULTS: All rats completed the experiment. The Movin sum score of the control group was significantly higher (p = 0.008) than that of the cilostazol group, with means of 11 ± 0.63 and 7.50 ± 1.15, respectively. Similarly, the mean Bonar score was significantly higher (p = 0.026) in the control group compared to the cilostazol group (8.33 ± 1.50 vs. 5.5 ± 0.54, respectively). Moreover, the Type I/Type III Collagen ratio was notably higher (p = 0.016) in the cilostazol group (52.2 ± 8.4) than in the control group (34.6 ± 10.2). The load to failure was substantially higher in the cilostazol group than in the control group (p = 0.034), suggesting that the tendons in the cilostazol group were stronger and exhibited greater resistance to failure. CONCLUSIONS: The results of this study suggest that cilostazol treatment significantly improves the biomechanical and histopathological parameters of the healing Achilles tendon in rats. Cilostazol might be a valuable supplementary therapy in treating Achilles tendon ruptures in humans. Additional clinical studies are, however, required to verify these outcomes.

Cost-effectiveness analysis of CYP2C19 genotype-guided antiplatelet therapy for patients with acute minor ischemic stroke and high-risk transient ischemic attack in China.

AIMS: The study aimed to estimate the cost-effectiveness of CYP2C19 genotype-guided antiplatelet therapy using cilostazol and ticagrelor as an alternative to clopidogrel, compared to conventional antiplatelet therapy with clopidogrel and aspirin. METHODS: A 90-day decision tree and 30-year Markov model were employed to assess the costs and quality-adjusted life years (QALYs) of personalized antiplatelet therapy for patients with minor ischemic stroke and high-risk transient ischemic attack, compared to conventional antiplatelet therapy in the Chinese healthcare system. The primary outcome was the incremental cost-effectiveness ratio (ICER). The data sources included clinical trials, published literature, official documents and local prices. One-way sensitivity analysis and probabilistic sensitivity analysis were performed to confirm the robustness of the findings. RESULTS: The base-case analysis indicated that the CYP2C19 genotype-guided antiplatelet strategy was cost-effective, and cilostazol group and ticagrelor group yielded an ICER of 3327.40 US dollars (USD)/QALY and 3426.92 USD/QALY, respectively, which were less than threshold. The one-way sensitivity analysis showed the results were robust, where the most sensitive parameter was the disability distribution in the modified Rankin scale 3-5. The probabilistic analysis showed that the CYP2C19 genotype-guided antiplatelet therapy with either cilostazol or ticagrelor was 100% cost-effective under the willingness-to-pay threshold. CONCLUSIONS: CYP2C19 genotype-guided antiplatelet therapy using cilostazol and ticagrelor as an alternative to clopidogrel appeared to be more cost-effective than conventional antiplatelet therapy for acute minor ischemic stroke and high-risk transient ischemic attack patients over 30 years in China.

Cilostazol versus Aspirin or Clopidogrel for Reducing Post-Stroke Aspiration Pneumonia: A Nationwide Retrospective Cohort Study.

INTRODUCTION: The association between the use of cilostazol as a post-stroke antiplatelet medication and a reduction in post-stroke pneumonia has been suggested. However, whether cilostazol has a greater preventive effect against post-stroke aspiration pneumonia (AP) than other antiplatelet medications remains unclear. Thus, this study aimed to evaluate whether cilostazol has a greater preventive effect against post-stroke AP than aspirin or clopidogrel. METHODS: Through the Japanese Diagnosis Procedure Combination database, we identified patients who were hospitalized for ischemic stroke between April 2012 and September 2019. We performed 1:1 propensity score matching between patients who received cilostazol alone at discharge and those who received aspirin or clopidogrel alone at discharge. The primary outcome was the 90-day readmission for post-stroke AP. The occurrence of recurrent ischemic stroke within 90 days was also evaluated. RESULTS: Among the 305,543 eligible patients with ischemic stroke, 65,141 (21%), 104,157 (34%), and 136,245 (45%) received cilostazol, aspirin, and clopidogrel, respectively. Propensity score matching generated 65,125 pairs. The cilostazol group had a higher proportion of 90-day post-stroke readmissions with AP than the aspirin or clopidogrel groups (1.5% vs. 1.2%, p < 0.001). The proportion of patients with recurrent ischemic stroke within 90 days was also higher in the cilostazol group (2.4% vs. 2.2%, p = 0.017). CONCLUSION: The present study suggests that cilostazol may not have a greater effect on preventing post-stroke AP within 90 days than other antiplatelet medications. Nevertheless, further randomized controlled trials with longer follow-up periods are warranted.

Second messenger signalling bypasses CGRP receptor blockade to provoke migraine attacks in humans.

There are several endogenous molecules that can trigger migraine attacks when administered to humans. Notably, calcitonin gene-related peptide (CGRP) has been identified as a key player in a signalling cascade involved in migraine attacks, acting through the second messenger cyclic adenosine monophosphate (cAMP) in various cells, including intracranial vascular smooth muscle cells. However, it remains unclear whether intracellular cAMP signalling requires CGRP receptor activation during a migraine attack in humans. To address this question, we conducted a randomized, double-blind, placebo-controlled, parallel trial using a human provocation model involving the administration of CGRP and cilostazol in individuals with migraine pretreated with erenumab or placebo. Our study revealed that migraine attacks can be provoked in patients by cAMP-mediated mechanisms using cilostazol, even when the CGRP receptor is blocked by erenumab. Furthermore, the dilation of cranial arteries induced by cilostazol was not influenced by the CGRP receptor blockade. These findings provide clinical evidence that cAMP-evoked migraine attacks do not require CGRP receptor activation. This discovery opens up new possibilities for the development of mechanism-based drugs for the treatment of migraine.

Cilostazol improves the prognosis after hepatectomy in rats with sinusoidal obstruction syndrome.

BACKGROUND AND AIM: Safe radical hepatectomy is important for patients with colorectal liver metastases complicated by sinusoidal obstruction syndrome (SOS) after oxaliplatin-based chemotherapy. This study aimed to investigate the impact of preoperative administration of cilostazol (CZ), an oral selective phosphodiesterase III inhibitor, on hepatectomy in rat SOS model. MATERIAL AND METHODS: Rats were divided into NL (normal liver), SOS (monocrotaline [MCT]-treated), and SOS + CZ (MCT + CZ-treated) groups. MCT or CZ was administered orally, and a 30% partial hepatectomy was performed 48 h after MCT administration. Postoperative survival rates were evaluated (n = 9, for each). Other rats were sacrificed on postoperative days (POD) 1 and 3 and evaluated histologically, immunohistochemically, biochemically, and using transmission electron microscopy (TEM), focusing particularly on SOS findings, liver damage, and liver sinusoidal endothelial cell (LSEC) injury. RESULTS: The cumulative 10-day postoperative survival rate was significantly higher in the SOS + CZ group than in the SOS group (88.9% vs 33.3%, P = 0.001). Total SOS scores were significantly lower in the SOS + CZ group than in the SOS group on both POD 1 and 3. Serum biochemistry and immunohistochemistry showed that CZ reduced liver damage after hepatectomy. TEM revealed that LSECs were significantly preserved morphologically in the SOS + CZ group than in the SOS group on POD 1 (86.1 ± 8.2% vs 63.8 ± 9.3%, P = 0.003). CONCLUSION: Preoperative CZ administration reduced liver injury by protecting LSECs and improved the prognosis after hepatectomy in rats with SOS.

Cytosolic DNA initiates a vicious circle of aging-related endothelial inflammation and mitochondrial dysfunction via STING: the inhibitory effect of Cilostazol.

Endothelial senescence, aging-related inflammation, and mitochondrial dysfunction are prominent features of vascular aging and contribute to the development of aging-associated vascular disease. Accumulating evidence indicates that DNA damage occurs in aging vascular cells, especially in endothelial cells (ECs). However, the mechanism of EC senescence has not been completely elucidated, and so far, there is no specific drug in the clinic to treat EC senescence and vascular aging. Here we show that various aging stimuli induce nuclear DNA and mitochondrial damage in ECs, thus facilitating the release of cytoplasmic free DNA (cfDNA), which activates the DNA-sensing adapter protein STING. STING activation led to a senescence-associated secretory phenotype (SASP), thereby releasing pro-aging cytokines and cfDNA to further exacerbate mitochondrial damage and EC senescence, thus forming a vicious circle, all of which can be suppressed by STING knockdown or inhibition. Using next-generation RNA sequencing, we demonstrate that STING activation stimulates, whereas STING inhibition disrupts pathways associated with cell senescence and SASP. In vivo studies unravel that endothelial-specific Sting deficiency alleviates aging-related endothelial inflammation and mitochondrial dysfunction and prevents the development of atherosclerosis in mice. By screening FDA-approved vasoprotective drugs, we identified Cilostazol as a new STING inhibitor that attenuates aging-related endothelial inflammation both in vitro and in vivo. We demonstrated that Cilostazol significantly inhibited STING translocation from the ER to the Golgi apparatus during STING activation by targeting S162 and S243 residues of STING. These results disclose the deleterious effects of a cfDNA-STING-SASP-cfDNA vicious circle on EC senescence and atherogenesis and suggest that the STING pathway is a promising therapeutic target for vascular aging-related diseases. A proposed model illustrates the central role of STING in mediating a vicious circle of cfDNA-STING-SASP-cfDNA to aggravate age-related endothelial inflammation and mitochondrial damage.

The Use and Impact of Cilostazol on Patients Undergoing Endovascular Peripheral Interventions.

BACKGROUND: Cilostazol is used for the treatment of intermittent claudication. The impact of cilostazol on the outcomes of peripheral vascular interventions (PVIs) remains controversial. This study assesses the use and impact of cilostazol on patients undergoing PVI for peripheral arterial disease (PAD). METHODS: The Vascular Quality Initiative (VQI) database files for PVI were reviewed. Patients with PAD who underwent PVI for chronic limb threatening-ischemia or claudication were included and divided based on the use of cilostazol preoperatively. After propensity matching for patient demographics and comorbidities, the short-term and long-term outcomes of the 2 groups (preoperative cilostazol use versus no preoperative cilostazol use) were compared. The Kaplan-Meier method was used to determine outcomes. RESULTS: A total of 245,309 patients underwent PVI procedures and 6.6% (N = 16,366) were on cilostazol prior to intervention. Patients that received cilostazol were more likely to be male (62% vs 60%; P < 0.001), White (77% vs. 75%; P < 0.001), and smokers (83% vs. 77%; P < 0.001). They were less likely to have diabetes mellitus (50% vs. 56%; P < 0.001) and congestive heart failure (14% vs. 23%; P < 0.001). Patient on cilostazol were more likely to be treated for claudication (63% vs. 40%, P < 0.001), undergo prior lower extremity revascularization (55% vs. 51%, P < 0.001) and less likely to have undergone prior minor and major amputation (10% vs. 19%; P < 0.001) compared with patients who did not receive cilostazol. After 3:1 propensity matching, there were 50,265 patients included in the analysis with no differences in baseline characteristics. Patients on cilostazol were less likely to develop renal complications and more likely to be discharged home. Patients on cilostazol had significantly lower rates of long-term mortality (11.5% vs. 13.4%, P < 0.001 and major amputation (4.0% vs. 4.7%, P = 0.022). However, there were no significant differences in rates of reintervention, major adverse limb events, or patency after PVI. Amputation-free survival rates were significantly higher for patients on cilostazol, after 4 years of follow up (89% vs. 87%, P = 0.03). CONCLUSIONS: Cilostazol is underutilized in the VQI database and seems to be associated with improved amputation-free survival. Cilostazol therapy should be considered in all patients with PAD who can tolerate it prior to PVI.

Treatment factors to suppress delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage based on VASOGRADE: multicenter cohort study.

Delayed cerebral ischemia (DCI) is one of the most important outcome determinants for aneurysmal subarachnoid hemorrhage (aSAH). VASOGRADE, which combines World Federation of Neurological Surgeons grade and modified Fisher grade, is a useful scale for predicting DCI after aSAH. However, no studies have investigated whether VASOGRADE influences the treatment options. We retrospectively analyzed 781 aSAH patients who were prospectively enrolled in 9 primary stroke centers from 2013 to 2021. The total cohort consisted of 76 patients (9.7%) with VASOGRADE-Green, 390 patients (49.9%) with VASOGRADE-Yellow, and 315 patients (40.3%) with VASOGRADE-Red. Worse VASOGRADE had higher incidences of DCI, which occurred in 190 patients (24.3%). As only 5 patients (6.6%) with VASOGRADE-Green developed DCI, we searched for DCI-associated factors in patients with VASOGRADEs-Yellow and -Red. Multivariate analyses revealed independent treatment factors suppressing DCI as follows: no postoperative hemorrhagic complication, combined administration of fasudil hydrochloride and cilostazol, combination of clipping and cisternal drainage, and coiling for VASOGRADE-Yellow; and clipping, and administration of fasudil hydrochloride with or without cilostazol for VASOGRADE-Red. The findings suggest that treatment strategies should be determined based on VASOGRADE to prevent DCI after aSAH.

Beyond nimodipine: advanced neuroprotection strategies for aneurysmal subarachnoid hemorrhage vasospasm and delayed cerebral ischemia.

The clinical management of aneurysmal subarachnoid hemorrhage (SAH)-associated vasospasm remains a challenge in neurosurgical practice, with its prevention and treatment having a major impact on neurological outcome. While considered a mainstay, nimodipine is burdened by some non-negligible limitations that make it still a suboptimal candidate of pharmacotherapy for SAH. This narrative review aims to provide an update on the pharmacodynamics, pharmacokinetics, overall evidence, and strength of recommendation of nimodipine alternative drugs for aneurysmal SAH-associated vasospasm and delayed cerebral ischemia. A PRISMA literature search was performed in the PubMed/Medline, Web of Science, ClinicalTrials.gov, and PubChem databases using a combination of the MeSH terms "medical therapy," "management," "cerebral vasospasm," "subarachnoid hemorrhage," and "delayed cerebral ischemia." Collected articles were reviewed for typology and relevance prior to final inclusion. A total of 346 articles were initially collected. The identification, screening, eligibility, and inclusion process resulted in the selection of 59 studies. Nicardipine and cilostazol, which have longer half-lives than nimodipine, had robust evidence of efficacy and safety. Eicosapentaenoic acid, dapsone and clazosentan showed a good balance between effectiveness and favorable pharmacokinetics. Combinations between different drug classes have been studied to a very limited extent. Nicardipine, cilostazol, Rho-kinase inhibitors, and clazosentan proved their better pharmacokinetic profiles compared with nimodipine without prejudice with effective and safe neuroprotective role. However, the number of trials conducted is significantly lower than for nimodipine. Aneurysmal SAH-associated vasospasm remains an area of ongoing preclinical and clinical research where the search for new drugs or associations is critical.

Letter to editor: Beyond nimodipine: advanced neuroprotection strategies for aneurysmal subarachnoid hemorrhage vasospasm and delayed cerebral ischemia.

This critique discusses neuroprotective strategies for aneurysmal subarachnoid hemorrhage (SAH), excluding Nimodipine, emphasizing alternatives like verapamil, albumin, and cilostazol. While these options show potential, their efficacy lacks robust confirmation from randomized controlled trials (RCTs), relying mainly on observational studies and small trials. The letter underscores the need for comprehensive safety assessments and long-term outcome studies to enhance practical application. Highlighting ongoing trials and emerging therapies like clazosentan and TAK-044, it advocates for future research directions focused on large-scale RCTs and combination therapies, such as cilostazol and Nimodipine, which have demonstrated synergistic benefits in reducing delayed cerebral ischemia (DCI) and improving patient outcomes.

Letter to the editor: "Beyond nimodipine: advanced neuroprotection strategies for aneurysmal subarachnoid hemorrhage vasospasm and delayed cerebral ischemia".

This letter commends the article by Luzzi et al. on alternative neuroprotection strategies for aneurysmal subarachnoid hemorrhage (SAH). It highlights the pharmacological advantages of nicardipine, cilostazol, and clazosentan over nimodipine in managing cerebral vasospasm and delayed cerebral ischemia. Emphasizing the need for personalized medicine, it advocates for integrating genetic screening and advanced monitoring techniques to tailor treatments to individual patient profiles. This approach could significantly improve clinical outcomes by optimizing drug efficacy and minimizing adverse effects.

Cilostazol for peripheral arterial disease - a position paper from the Italian Society for Angiology and Vascular Medicine.

Cilostazol is a quinolinone-derivative selective phosphodiesterase inhibitor and is a platelet-aggregation inhibitor and arterial vasodilator for the symptomatic treatment of intermittent claudication (IC). Cilostazol has been shown to improve walking distance for patients with moderate to severe disabling intermittent claudication who do not respond to exercise therapy and who are not candidates for vascular surgical or endovascular procedures. Several studies evaluated the pharmacological effects of cilostazol for restenosis prevention and indicated a possible effect on re-endothelialization mediated by hepatocyte growth factor and endothelial precursor cells, as well as inhibiting smooth muscle cell proliferation and leukocyte adhesion to endothelium, thereby exerting an anti-inflammatory effect. These effects may suggest a potential effectiveness of cilostazol in preventing restenosis and promoting the long-term outcome of revascularization interventions. This review aimed to point out the role of cilostazol in treating patients with peripheral arterial disease, particularly with IC, and to explore its possible role in restenosis after lower limb revascularization.

The Role of Cilostazol, a Phosphodiesterase-3 Inhibitor, in the Development of Atherosclerosis and Vascular Biology: A Review with Meta-Analysis.

Atherosclerotic cardiovascular disease (ASCVD) stands as the leading global cause of mortality. Addressing this vital and pervasive condition requires a multifaceted approach, in which antiplatelet intervention plays a pivotal role, together with antihypertensive, antidiabetic, and lipid-lowering therapies. Among the antiplatelet agents available currently, cilostazol, a phosphodiesterase-3 inhibitor, offers a spectrum of pharmacological effects. These encompass vasodilation, the impediment of platelet activation and aggregation, thrombosis inhibition, limb blood flow augmentation, lipid profile enhancement through triglyceride reduction and high-density lipoprotein cholesterol elevation, and the suppression of vascular smooth muscle cell proliferation. However, the role of cilostazol has not been clearly documented in many guidelines for ASCVD. We comprehensively reviewed the cardiovascular effects of cilostazol within randomized clinical trials that compared it to control or active agents and involved individuals with previous coronary artery disease or stroke, as well as those with no previous history of such conditions. Our approach demonstrated that the administration of cilostazol effectively reduced adverse cardiovascular events, although there was less evidence regarding its impact on myocardial infarction. Most studies have consistently reported its favorable effects in reducing intermittent claudication and enhancing ambulatory capacity in patients with peripheral arterial disease. Furthermore, cilostazol has shown promise in mitigating restenosis following coronary stent implantation in patients with acute coronary syndrome. While research from more diverse regions is still needed, our findings shed light on the broader implications of cilostazol in the context of atherosclerosis and vascular biology, particularly for individuals at high risk of ASCVD.

Cilostazol Attenuates Hepatic Steatosis and Intestinal Disorders in Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in the world, which begins with liver lipid accumulation and is associated with metabolic syndrome. Also, the name chosen to replace NAFLD was metabolic dysfunction-associated steatotic liver disease (MASLD). We performed focused drug screening and found that Cilostazol effectively ameliorated hepatic steatosis and might offer potential for NAFLD treatment. Our aim was to investigate the therapeutic effects of Cilostazol on the glycolipid metabolism and intestinal flora in NAFLD mice and explore the specific mechanism. In this study, 7-week-old male C57BL/6J mice were fed a high-fat diet (HFD) for 8 weeks to induce NAFLD, and then treated with intragastric administration for 12 weeks. The results showed that Cilostazol inhibited liver lipid de novo synthesis by regulating the AMPK-ACC1/SCD1 pathway and inhibited liver gluconeogenesis by the AMPK-PGC1α-G6P/PEPCK pathway. Cilostazol improved the intestinal flora diversity and intestinal microbial composition in the NAFLD mice, and specifically regulated Desulfovibrio and Akkermansia. In addition, Cilostazol increased the level of short-chain fatty acids in the NAFLD mice to a level similar to that in the blank Control group. Cilostazol reduces liver lipid accumulation in NAFLD mice by improving glucose and lipid metabolism disorders and intestinal dysfunction, thereby achieving the purpose of treating NAFLD.

Cilostazol Ameliorates Motor Dysfunction and Schwann Cell Impairment in Streptozotocin-Induced Diabetic Rats.

This study investigated the effects of cilostazol on motor dysfunction, spinal motor neuron abnormalities, and schwannopathy in rats with diabetes. Diabetes mellitus (DM) was induced in rats via femoral intravenous streptozotocin (STZ) injection (60 mg/kg). After successful DM induction, cilostazol was administered on day 15 via oral gavage (100 mg/kg/day) for 6 weeks until sacrifice. Behavioral assays, including motor function, were performed weekly. The sciatic nerve, L5 spinal cord, and spinal ventral root were collected to evaluate the expression of the glial fibrillary acidic protein (GFAP), myelin protein zero (P0), and choline acetyltransferase (ChAT) by immunofluorescence and Western blotting. DM rats displayed decreased running speeds, running distances, and toe spread but increased foot pressure. In addition, loss of non-myelinating Schwann cells and myelin sheaths was observed in the sciatic nerve and L5 spinal ventral root. Reduced numbers of motor neurons were also found in the L5 spinal ventral horn. Cilostazol administration significantly potentiated running speed and distance; increased hind paw toe spread; and decreased foot pressure. In the sciatic nerve and L5 spinal ventral root, cilostazol treatment significantly improved non-myelinated Schwann cells and increased myelin mass. ChAT expression in motor neurons in the spinal ventral horn was improved, but not significantly. Cilostazol administration may protect sensorimotor function in diabetic rats.

Cilostazol Stimulates Angiogenesis and Accelerates Fracture Healing in Aged Male and Female Mice by Increasing the Expression of PI3K and RUNX2.

Fracture healing in the aged is associated with a reduced healing capacity, which often results in delayed healing or non-union formation. Many factors may contribute to this deterioration of bone regeneration, including a reduced 'angiogenic trauma response'. The phosphodiesterase-3 (PDE-3) inhibitor cilostazol has been shown to exert pro-angiogenic and pro-osteogenic effects in preclinical studies. Therefore, we herein analyzed in a stable closed femoral fracture model whether this compound also promotes fracture healing in aged mice. Forty-two aged CD-1 mice (age: 16-18 months) were daily treated with 30 mg/kg body weight cilostazol (n = 21) or vehicle (control, n = 21) by oral gavage. At 2 and 5 weeks after fracture, the femora were analyzed by X-ray, biomechanics, micro-computed tomography (µCT), histology, immunohistochemistry, and Western blotting. These analyses revealed a significantly increased bending stiffness at 2 weeks (2.2 ± 0.4 vs. 4.3 ± 0.7 N/mm) and an enhanced bone formation at 5 weeks (4.4 ± 0.7 vs. 9.1 ± 0.7 mm3) in cilostazol-treated mice when compared to controls. This was associated with a higher number of newly formed CD31-positive microvessels (3.3 ± 0.9 vs. 5.5 ± 0.7 microvessels/HPF) as well as an elevated expression of phosphoinositide-3-kinase (PI3K) (3.6 ± 0.8 vs. 17.4 ± 5.5-pixel intensity × 104) and runt-related transcription factor (RUNX)2 (6.4 ± 1.2 vs. 18.2 ± 2.7-pixel intensity × 104) within the callus tissue. These findings indicate that cilostazol accelerates fracture healing in aged mice by stimulating angiogenesis and the expression of PI3K and RUNX2. Hence, cilostazol may represent a promising compound to promote bone regeneration in geriatric patients.

Theoretical Investigations on Free Energy of Binding Cilostazol with Different Cyclodextrins as Complex for Selective PDE3 Inhibition.

Cilostazol is a phosphodiesterase III inhibitor characterized by poor solubility. This limitation can be overcome by using a drug carrier capable of delivering the drug to the target site. Cyclodextrins are essential as drug carriers because of their outstanding complexation abilities and their capacity to improve drug bioavailability. This study comprises two stages: The first involves verifying different cyclodextrins and their complexation abilities towards cilostazol. This was accomplished using molecular docking simulations (MDS) and density functional theory (DFT). Both techniques indicate that the largest Sulfobutyl Ether-ß-Cyclodextrin forms the most stable complex with cilostazol. Additionally, other important parameters of the complex are described, including binding sites, dominant interactions, and thermodynamic parameters such as complexation enthalpy, Gibbs free energy, and Gibbs free energy of solvation. The second stage involves a binding study between cilostazol and Phosphodiesterse3 (PDE3). This study was conducted using molecular docking simulations, and the most important energetic parameters are detailed. This is the first such report, and we believe that the results of our predictions will pave the way for future drug development efforts using cyclodextrin-cilostazol complexes as potential therapeutics.