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Journal of Biomolecular Structure &... Jul 2023Enhancing sperm motility has immensely benefited assisted conception methods. Phosphodiesterases (PDE) break the second messenger cAMP, and therefore, inhibition of...
Enhancing sperm motility has immensely benefited assisted conception methods. Phosphodiesterases (PDE) break the second messenger cAMP, and therefore, inhibition of their catalytic activity enhances the sperm motility through maintaining cAMP homeostasis in sperm. In view of identifying the molecules that could inhibit PDE functioning in spermatozoa, we aimed to evaluate the phosphodiesterase inhibitors (PDEI) - xanthine derivatives - acefylline, dyphylline and proxyphylline to repurpose them for assisted reproductive technology. These are available in the market as pharmaceutical agents to treat mainly respiratory system diseases. Based on the structure guided studies, we predicted that these molecules bind to the cAMP binding catalytic pocket of PDE enzymes, and further molecular dynamics simulation analysis indicated that these molecules form the stable complexes. Isothermal titration calorimetry studies revealed that acefylline has better affinity towards PDE4A, PDE4D and PDE10A, when compared to dyphylline and proxyphylline. In addition, studies corroborated binding studies that acefylline has much superior sperm motility enhancement property on human ejaculated spermatozoa and mouse testicular spermatozoa compared to dyphylline and proxyphylline.Communicated by Ramaswamy H. Sarma.
Topics: Animals; Mice; Male; Humans; Dyphylline; Sperm Motility; Semen; Phosphodiesterase Inhibitors; Spermatozoa; Phosphoric Diester Hydrolases
PubMed: 35696450
DOI: 10.1080/07391102.2022.2085802 -
Digestive Diseases and Sciences Apr 2024To describe hepatotoxicity due to amiodarone and dronedarone from the DILIN and the US FDA's surveillance database.
OBJECTIVE
To describe hepatotoxicity due to amiodarone and dronedarone from the DILIN and the US FDA's surveillance database.
METHODS
Hepatotoxicity due to amiodarone and dronedarone enrolled in the U.S. Drug Induced Liver Injury Network (DILIN) from 2004 to 2020 are described. Dronedarone hepatotoxicity cases associated with liver biopsy results were obtained from the FDA Adverse Event Reporting System (FAERS) from 2009 to 2020.
RESULTS
Among DILIN's 10 amiodarone and 3 dronedarone DILIN cases, the latency for amiodarone was longer than with dronedarone (388 vs 119 days, p = 0.50) and the median ALT at DILI onset was significantly lower with amiodarone (118 vs 1191 U/L, p = 0.05). Liver biopsies in five amiodarone cases showed fibrosis, steatosis, and numerous Mallory-Denk bodies. Five patients died although only one from liver failure. One patient with dronedarone induced liver injury died of a non-liver related cause. Nine additional cases of DILI due to dronedarone requiring hospitalization were identified in the FAERS database. Three patients developed liver injury within a month of starting the medication. Two developed acute liver failure and underwent urgent liver transplant, one was evaluated for liver transplant but then recovered spontaneously, while one patient with cirrhosis died of liver related causes.
CONCLUSION
Amiodarone hepatotoxicity resembles that seen in alcohol related liver injury, with fatty infiltration and inflammation. Dronedarone is less predictable, typically without fat and with a shorter latency of use before presentation. These differences may be explained, in part, by the differing pharmacokinetics of the two drugs leading to different mechanisms of hepatotoxicity.
Topics: Humans; Dronedarone; Amiodarone; Anti-Arrhythmia Agents; Dyphylline; Chemical and Drug Induced Liver Injury
PubMed: 38416280
DOI: 10.1007/s10620-023-08251-2 -
Biomolecules Dec 2023Gout is characterized by the formation of monosodium urate crystals in peripheral joints. We carried out laboratory studies to investigate the effect of adding nine...
Gout is characterized by the formation of monosodium urate crystals in peripheral joints. We carried out laboratory studies to investigate the effect of adding nine different methylxanthines and two different methylated uric acid derivatives on the development of these crystals over the course of 96 h in a medium whose composition was similar to that of synovial fluid. Our results showed that 7-methylxanthine reduced or totally prevented crystal formation; 1-methylxanthine, 3-methylxanthine, 7-methyluric acid, and 1,3-dimethyluric acid had weaker effects, and the other molecules had no apparent effect. The presented results indicate that a 7-methylxanthine concentration of about 6 × 10 M (10 mg/L) prevented the formation of crystals for an initial urate concentration of 1.78 × 10 M (300 mg/L) in the presence of 0.4 M of Na for 96 h at 25 °C and a pH of 7.4. We attribute these results to alterations in thermodynamics, not kinetics. Our results suggest that prevention of crystallization in vivo could be achieved by direct oral administration of 7-methylxanthine or other methylxanthines that are metabolized to 7-methylxanthine. For example, the hepatic metabolism of theobromine leads to significant plasma levels of 7-methylxanthine (14% of the initial theobromine concentration) and 3-methylxanthine (6% of the initial theobromine concentration); however, 7-methyluric acid is present at very low concentrations in the plasma. It is important to consider that several of the specific molecules we examined (theobromine, caffeine, theophylline, dyphylline, etophylline, and pentoxifylline) did not directly affect crystallization.
Topics: Uric Acid; Theobromine; Solubility; Caffeine
PubMed: 38136640
DOI: 10.3390/biom13121769 -
Tierarztliche Praxis. Ausgabe K,... Apr 2024In 2023, 2 novel pharmaceutical agents for small animals were released on the German market: the structural but non-functional analog of the inhibitory neurotransmitter...
In 2023, 2 novel pharmaceutical agents for small animals were released on the German market: the structural but non-functional analog of the inhibitory neurotransmitter gamma-aminobutyric acid pregabalin with an anxiolytic active component and the dopamine agonist ropinirole in form of eye drops to induce vomiting. Two established active veterinary pharmaceutical ingredients became available for additional species: The phosphorus compound butafosfan was additionally approved for horses, dogs and cats and the mineral sodium chloride as an isotonic sodium chloride solution was also approved for rabbits and guinea pigs. In addition, for small animals, there were new releases of an agent (dexamethasone) in a novel pharmaceutical formulation, one drug with a new route of administration (hydrocortisone aceponate), one drug with a new content of the active ingredient (firocoxib) as well as one veterinary drug with a new combination of active ingredients in a novel pharmaceutical formulation (gentamicin+mometasone+posaconazole). Furthermore, one combination of active ingredients (diprophylline+heptaminol) is available on the market for small animals again.
Topics: Animals; Veterinary Drugs; Dogs; Cats; Horses; Germany; Rabbits
PubMed: 38701806
DOI: 10.1055/a-2291-7019 -
Tierarztliche Praxis. Ausgabe G,... Apr 2024In 2023, no new active pharmaceutical ingredients were released on the German market for horses and food-producing animals. Two established veterinary active...
In 2023, no new active pharmaceutical ingredients were released on the German market for horses and food-producing animals. Two established veterinary active pharmaceutical ingredients became available for additional species: The phosphorus compound butafosfan was also approved for horses, dogs, and cats and the mineral sodium chloride as an isotonic sodium chloride solution was also approved for rabbits and guinea pigs. In addition, for small animals, there were new releases of an agent (pergolidmesilate) in a novel pharmaceutical formulation and a lower content of the active ingredient, one drug (fluralaner) in a smaller package size as well as one drug (oxalic acid dehydrate) with a new route of administration. Furthermore, one combination of active ingredients (diprophylline+heptaminol) is available on the market for horses and food producing animals again.
Topics: Animals; Horses; Veterinary Drugs; Germany; Dogs; Cats; Guinea Pigs; Rabbits
PubMed: 38701800
DOI: 10.1055/a-2291-7062