Natural Phosphodiesterase-4 Inhibitors with Potential Anti-Inflammatory Activities from Millettia dielsiana

The results of in silico screening of the 50 isolated compounds from Millettia dielsiana against the target proteins PDE4 (PDE4A, PDE4B, and PDE4D) showed binding affinity ranges from -5.81 to -11.56, -5.27 to -13.01, and -5.80 to -12.12 kcal mol-1, respectively, with median values of -8.83, -8.84, and -8.645 kcal mol-1, respectively. Among these compounds, Millesianin F was identified as the most promising PDE4A inhibitor due to its strongest binding affinity with the target protein PDE4A. (-11.56 kcal mol-1). This was followed by the compound 5,7,4'-trihydroxyisoflavone 7-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside (D50) with the binding affinity value of -11.35 kcal mol-1. For the target protein PDE4B, compound D50 exhibited the strongest binding affinity value of -13.01 kcal mol-1, while showing poorer inhibition ability for PDE4D. The 100 ns MD simulation examination (radius of gyration, Solvent Accessible Surface Area (SASA), Root-Mean-Square Deviation (RMSD), Root-Mean-Square Fluctuation (RMSF), and hydrogen bonding) was carried out to examine the overall stability and binding efficiency of the protein-ligand complex between compounds (Millesianin F, Millesianin G, Claclrastin-7-O-β-d-glucopyranoside, 7-hydroxy-4',6 dimethoxyisoflavone-7-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside, 7-hydroxy-4',8-dimethoxyisoflavone 7-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside, Odoratin-7-O-β-d-glucopyranoside, and 5,7,4'-trihydroxyisoflavone 7-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside) and PDE4 (A, B) subtype proteins. Compound D50 has shown strong anti-inflammatory activity, as evidenced by experimental results. It effectively inhibits PDE4B and PDE4D, with IC50 values of 6.56 ± 0.7 µM and 11.74 ± 1.3 µM, respectively. Additionally, it reduces NO production, with an IC50 value of 5.40 ± 0.9 µM. Based on these findings, it is promising and considered a potential novel anti-inflammatory drug for future development.

Pharmacological Management of Obesity in Patients with Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. A substantial proportion of patients with PCOS are either overweight or obese, and excess body weight aggravates the hormonal, reproductive and metabolic manifestations of PCOS. In recent years, several studies evaluated the role of various pharmacological agents in the management of obesity in this population. Most reports assessed glucagon-like peptide-1 receptor agonists and showed a substantial reduction in body weight. More limited data suggest that sodium-glucose cotransporter-2 inhibitors and phosphodiesterase-4 inhibitors might also be effective in the management of obesity in these patients. In the present review, we discuss the current evidence on the safety and efficacy of these agents in overweight and obese patients with PCOS.

Atopic Dermatitis - Current State of Research on Biological Treatment

Atopic dermatitis (AD) is the most common atopic disease in young children and most common skin disease in childhood. In the Polish population, the incidence of AD in the group of children aged 6–14 is about 4% and it is underestimated. The disease is chronic and recurrent, and the leading symptom is skin pruritus that in the mechanism of the vicious circle is accompanied by scratching that causes generalized infections. The overall problems lead to a decrease in the quality of life of the child and its parents and to an increased risk of psychosomatic diseases. The complex pathomechanism of AD is due to chronic inflammation of the skin, in which various cell phenotypes are involved. The management is comprehensive and it is aimed at reducing inflammation, improving the skin barrier function, reducing the symptoms of dryness and itching of the skin and secondarily improving the quality of life. The treatment includes intensive skincare, anti-inflammatory treatment based on the proactive use of topical glucocorticosteroids and topical calcineurin inhibitors. Periods of exacerbation of lesions require intensified treatment. In particularly severe, recurrent cases, treatment options can be extended to systemic immunosuppressive drugs, with awareness of their adverse effects. Previous year has brought significant progress in the current treatment of AD in the form of biological treatment. Cytokines and other mediators that play an important role in the pathogenesis of skin inflammation have become a target for new forms of therapy. Drugs for which interleukin (IL)-4 and IL-13 are the targets are particularly represented. Dupilumab is the first biological drug approved for the general treatment of children aged >12 years with moderate to severe AD. Another therapeutic option for topical use is crisaborole, a phosphodiesterase-4 inhibitor. This study presents the current state of research on biological drugs in AD.

Roflumilast counteracts DMH-induced preneoplastic colon damage in albino Wistar rats

OBJECTIVE

The study explored the chemoprophylactic potential of roflumilast against 1,2-dimethylhydrazine (DMH) actuated preneoplastic colon damage in albino Wistar rats.

METHODS

Animals were arbitrarily divided into five groups of six animals each. DMH was used to induce preneoplastic colon damage (20 mg/kg/7 days, subcutaneously, for 42 days). Roflumilast was administered subcutaneously at two doses (1 and 5 mg/kg/day, from day 28 to 42). At the end of the study, the animals were recorded for the electrocardiographic changes and heart rate variability (HRV) paradigms on 42nd day, using PowerLab system. Blood samples were collected from all the animals to measure hydrogen sulfide (H₂S) and nitric acid. The colon tissue was dissected out and analyzed for inflammatory markers, biochemical parameters including, superoxide dismutase, thiobarbituric acid reactive substances, catalase, and glutathione reductase and histopathology.

RESULTS

DMH caused derangement of HRV factors, abnormal antioxidant markers, and elevated levels of inflammatory markers. H₂S and nitric oxide levels upsurge in DMH-treated rats and promoted preneoplastic damage. Histopathologically, loss of crypts, goblet cells, and distorted lamina propria were observed in toxic group. Treatment with roflumilast was able to curtail down oxidative stress and inflammatory markers and stabilitate the hemodynamic derangements as well as was able to restore the normal architecture of colonic mucosa.

CONCLUSION

The findings from the present study conclude that treatment with roflumilast positively modulates the preneoplastic colon damage.

Thalidomide and Phosphodiesterase 4 Inhibitors as Host Directed Therapeutics for Tuberculous Meningitis: Insights From the Rabbit Model

Tuberculous meningitis (TBM) is the most devastating form of extrapulmonary Mycobacterium tuberculosis infection in humans. Severe inflammation and extensive tissue damage drive the morbidity and mortality of this manifestation of tuberculosis (TB). Antibiotic treatment is ineffective at curing TBM due to variable and incomplete drug penetration across the blood-brain barrier (BBB) and blood-cerebrospinal fluid (CSF) barriers. Adjunctive corticosteroid therapy, used to dampen the inflammation, and the pathologic manifestation of TBM, improves overall survival but does not entirely prevent the morbidity of the disease and has significant toxicities, including immune-suppression. The rabbit has served as a fit for purpose experimental model of human TBM since the early 1900s due to the similarity in the developmental processes of the brain, including neuronal development, myelination, and microglial functions between humans and rabbits. Consistent with the observations made in humans, proinflammatory cytokines, including TNF-α, play a critical role in the pathogenesis of TBM in rabbits focusing the attention on the utility of TNF-α inhibitors in treating the disease. Thalidomide, an inhibitor of monocyte-derived TNF-α, was evaluated in the rabbit model of TBM and shown to improve survival and reduce inflammation of the brain and the meninges. Clinical studies in humans have also shown a beneficial response to thalidomide. However, the teratogenicity and T-cell activation function of the drug limit the use of thalidomide in the clinic. Thus, new drugs with more selective anti-inflammatory properties and a better safety profile are being developed. Some of these candidate drugs, such as phosphodiesterase-4 inhibitors, have been shown to reduce the morbidity and increase the survival of rabbits with TBM. Future studies are needed to assess the beneficial effects of these drugs for their potential to improve the current treatment strategy for TBM in humans.

MONOCLONAL ANTIBODY THERAPIES for Atopic Dermatitis: Where Are We Now in the Spectrum of Disease Management?

Atopic dermatitis (AD) is a chronic disorder that requires thorough patient education and a therapeutic management strategy designed to control flares, decrease recurrences, and reduce pruritus. In cases that cannot be controlled by proper skin care and barrier repair, topical therapy, and avoidance of triggers, systemic therapy is often required to control flares and maintain remission. It is important for clinicians to avoid becoming overly dependent on the intermittent use of systemic corticosteroid therapy to control flares, without incorporating other treatment options that might more optimally control AD over time. This article provides an overview of systemic therapies, including conventional oral therapy options and injectable biologic agents, that modulate the immune dysregulation in AD. Major emphasis is placed on the monoclonal antibodies currently available (e.g., dupilumab) for the treatment of AD, as well as those in latter stages of development, with a focus on agents targeting IL-4and/or IL-13.

Safety, tolerability, and pharmacokinetics of single and repeat ascending doses of CHF6001, a novel inhaled phosphodiesterase-4 inhibitor: two randomized trials in healthy volunteers

PURPOSE

The purpose of this study was to evaluate safety, tolerability, and pharmacokinetics (PK) of CHF6001, an inhaled phosphodiesterase-4 inhibitor.

MATERIALS AND METHODS

Two healthy volunteer, randomized, double-blind, placebo-controlled studies were conducted. In each, Part 1 evaluated single ascending doses, with PK sampling up to 48 hours post-dose; Part 2 evaluated multiple ascending doses (Study 1, 7 days; Study 2, 14 days), with PK sampling up to 24 hours post-dose on first and last day of each period. In Study 1, treatments were administered via single-dose dry-powder inhaler (SDDPI; Aerolizer): Part 1, 20, 100, 200, 400, 800, 1,600, and 2,000 µg or placebo; Part 2, 100, 300, 600, 1,200, and 1,600 µg or placebo once daily (OD). In Study 2, treatments were administered via multi-dose dry-powder inhaler (MDDPI; NEXThaler): Part 1, 2,400, 4,000, and 4,800 µg or placebo; Part 2, 1,200, 2,000, or 2,400 µg twice daily (BID) or placebo. Modeling and simulation then compared OD and BID dosing via MDDPI.

RESULTS

There was a clear correlation between CHF6001 dose and plasma concentration, following single and multiple doses and using SDDPI and MDDPI. CHF6001 plasma concentration area under the curve (AUC) was dose proportional, with steady state slopes of the fitted line of 0.95 (90% CI: 0.86, 1.04) for AUC0-24 h in Study 1, and 0.85 (90% CI: 0.38, 1.32) for AUC0-12 h in Study 2. Bioavailability waŝ30% higher with MDDPI than SDDPI. The PK simulation confirmed dose proportionality; the same total daily dose OD or BID via MDDPI resulted in similar 24 hours exposure, with BID dosing providing smaller fluctuation and lower maximum concentration. CHF6001 was well tolerated with no relationship between dose and adverse events.

CONCLUSION

CHF6001 demonstrated a good safety profile. There was a clear dose proportionality for systemic exposure, with higher bioavailability via MDDPI, suggesting that the MDDPI provides better pulmonary drug deposition. BID dosing was associated with a better exposure profile.

Pharmacological mechanism of roflumilast in the treatment of asthma-COPD overlap

Asthma-COPD overlap (ACO) is a type of incomplete obstructive airway disease that has a high incidence and mortality. Nevertheless, there is currently no clear definition of ACO and no effective intervention. The newly discovered phosphodiesterase-4 inhibitor, roflumilast, has shown initial efficacy for treating asthma, COPD, and ACO. The mechanism of roflumilast, however, remains unclear, and there has been no interpretation through systematic review to date. The determination of a definite mechanism of roflumilast will guide the clinician's decisions regarding medication use, standardized diagnosis, and treatment guidelines. For this reason, we have systematically reviewed the therapeutic mechanism of roflumilast for ACO and provided reference for the clinical application of roflumilast in ACO.

Rapid clearance of erythrodermic psoriasis with apremilast

Background

Apremilast is a new immunomodulatory drug, a small molecule inhibitor of PDE4, which down-regulates the expression of multiple pro-inflammatory cytokines, such as tumor necrosis factor alpha, interleukin 17, interleukin 23.

Main observations

We describe a case of a 54-year-old man with erythroderma in the course of psoriasis (PASI=49), with contraindications to other psoriasis therapies, in whom total clearance of skin lesions was achieved by day 20 after therapy with apremilast at a dose of 30 mg bid (ΔPASI = 100). The patient had a history of prior use of cyclosporine, methotrexate and adalimumab. His comorbidities included obesity, fatty liver and hypercholesterolemia.

Conclusion

In this case of erythroderma in the course of psoriasis apremilast led to total clearance of all cutaneous lesions.

Roflumilast: a review of its use in the treatment of COPD

COPD is a progressive condition involving chronic inflammation and parenchymal destruction with resulting airflow limitation. COPD is associated with worsening airflow limitation over time and increased frequency of COPD exacerbations, leading to increased mortality and morbidity. The effects of COPD extend beyond the lungs, as multiple comorbidities may occur with COPD, including cardiovascular disease, diabetes mellitus, osteoporosis, depression, and pneumonia. COPD exacerbations are associated with a rapid worsening of baseline symptoms that requires prompt management and may necessitate hospitalization in the case of a severe episode. Patients with COPD exacerbations require urgent management of symptoms to prevent further worsening, and preventative steps may be taken to help reduce the number and frequency of future exacerbations. Roflumilast is a potent and selective inhibitor of the enzyme phosphodiesterase-4 that targets the systemic inflammation associated with COPD. Roflumilast has a variety of anti-inflammatory effects including decreasing inflammatory mediators and the expression of cell surface markers and inhibition of apoptosis. Several clinical trials evaluating roflumilast in the treatment of COPD have demonstrated significant improvements from baseline versus placebo in lung function, including increases in mean pre- and postbronchodilator forced expiratory volume in 1 second and forced vital capacity. Data suggest that roflumilast reduces moderate to severe exacerbations with the benefit most well established in patients with severe disease. Given this evidence, roflumilast, as part of a combination regimen with long-acting bronchodilators, appears to be a reasonable treatment option for patients with severe to very severe COPD associated with chronic bronchitis and a history of exacerbations.

Roflumilast, a phosphodiesterase-4 inhibitor, induces phagocytic activity in Greek COPD patients

Background

A new approach to the treatment of COPD includes controlling inflammation because of its important role in exacerbation of the disease. Recently, roflumilast has been added as a therapeutic option for COPD. Roflumilast is an oral phosphodiesterase-4 inhibitor that targets inflammatory cells involved in triggering exacerbations of COPD. The objective of the current study was to evaluate roflumilast for its contribution to phagocytic activity in COPD patients.

Methods

Twenty-one patients diagnosed with COPD received roflumilast once daily for 6 months in combination with fluticasone (an inhaled corticosteroid), salmeterol (a long-acting β2-agonist), and tiotropium (a long-acting muscarinic antagonist) or combinations of these agents. The main inclusion criterion was stable disease for at least the previous 30 days. Neutrophils and spirometric changes, ie, forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC), were measured in the COPD patients at indicated time points. The first sample was taken before receiving roflumilast, the second 3 months later, and the third after 6 months. Examination of defective phagocytosis was done by flow cytometry using a FagoFlowEx^® kit. The statistical analysis was performed using Statistica software.

Results

Our results indicate that phagocytic activity was increased after 3 and 6 months of treatment when compared with baseline (P<0.001). Similarly, FVC and FEV₁ were also increased during the 6-month period, but only FVC differed significantly from baseline (P<0.001).

Conclusion

Although the number of patients in this study was limited, our results indicate that roflumilast induces phagocytic activity, which improves lung function.