Molecular Docking, Synthesis, and Tyrosinase Inhibition Activity of Acetophenone Amide: Potential Inhibitor of Melanogenesis

Tyrosinase and its related proteins are responsible for pigmentation disorders, and inhibiting tyrosinase is an established strategy to treat hyperpigmentation. The carbonyl scaffolds can be effective inhibitors of tyrosinase activity, and the fact that both benzoic and cinnamic acids are safe natural substances with such a scaffolded structure, it was speculated that hydroxyl-substituted benzoic and cinnamic acid derivatives may exhibit potent tyrosinase inhibitory activity. These moieties were incorporated into new chemotypes that displayed in vitro inhibitory effect against mushroom tyrosinase with a view to explore antimelanogenic ingredients. The most active compound, 2-((3-acetylphenyl)amino)-2-oxoethyl(E)-3-(2,4-dihydroxyphenyl)acrylate (5c), inhibited mushroom tyrosinase with an IC50 of 0.0020 ± 0.0002 μ M , while 2-((3-acetylphenyl)amino)-2-oxoethyl 2,4-dihydroxybenzoate (3c) had an IC50 of 27.35 ± 3.6 μ M in comparison to the positive control arbutin and kojic acid with a tyrosinase inhibitory activity of IC50 of 191.17 ± 5.5 μ M and IC50 of 16.69 ± 2.8 μ M , respectively. Analysis of enzyme kinetics revealed that 5c is a competitive and reversible inhibitor with dissociation constant (Ki) value 0.0072 μM. In silico docking studies with mushroom tyrosinase (PDB ID 2Y9X) predicted possible binding modes in the enzymatic pocket for these compounds. The orthohydroxyl of the cinnamic acid moiety of 5c is predicted to form hydrogen bond with the active site side chain carbonyl of Asn 260 (2.16 Å) closer to the catalytic site Cu ions. The acetyl carbonyl is picking up another hydrogen bond with Asn 81 (1.90 Å). The inhibitor 5c passed the panassay interference (PAINS) alerts. This study presents the potential of hydroxyl-substituted benzoic and cinnamic acids and could be beneficial for various cosmetic formulations.

Treatment of cognitive impairment in arterial hypertension

Cognitive impairment (CI) is one of the earliest and most frequent neurological disorders in patients with arterial hypertension. Arterial hypertension is a leading modifiable risk factor for stroke and cerebral microangiopathy, which underlies the development of non-stroke associated CI. Antihypertensive therapy plays an essential role in preventing the development and slowing the progression of CI by controlling blood pressure. The review discusses the use of memantine – a reversible inhibitor of NMDA receptors (akatinol memantine) – in vascular CI.

Development of a Capillary Electrophoretic Method for the Determination of Huperzine A Concentration in Vietnamese Huperzia serrata

Huperzine A, isolated from Huperzia serrata, is a potent, specific, and reversible inhibitor of acetylcholinesterase with high efficiency and low toxicity. To evaluate the presence of huperzine A in Vietnamese H serrata, a reliable capillary zone electrophoresis method was developed. The analytical conditions were established using 80 mM ammonium acetate buffer, pH 6.0, hydrodynamic injection at 50 mbar for 5 s, applied voltage of 20 kV, temperature at 25 °C, uncoated fused-silica capillary, 56 cm (50 cm effective length) × 70 µm inner diameter, and ultraviolet detection at 310 nm. The recovery rates ranged from 98.05% to 100.64%, with a relative standard deviation <2%. Good linear regression was observed in the concentration range of 1 to 500 µg/mL, with a correlation coefficient of 0.9994. The limit of detection and limit of quantification were 0.33 and 1.0 µg/mL, respectively. These results demonstrate that this method is simple, selective, and suitable for performing quality control for huperzine A derived from Vietnamese H serrata.

Huperzia serrata Extract ‘NSP01’ With Neuroprotective Effects-Potential Synergies of Huperzine A and Polyphenols

Huperzia serrata (Thunb.) Trevis is widely used in traditional asiatic medicine to treat many central disorders including, schizophrenia, cognitive dysfunction, and dementia. The major alkaloid, Huperzine A (HA), of H. serrata is a well-known competitive reversible inhibitor of acetylcholinesterase (AChE) with neuroprotective effects. Inspired by the tradition, we developed a green one-step method using microwave assisted extraction to generate an extract of H. serrata, called NSP01. This green extract conserves original neuropharmacological activity and chemical profile of traditional extract. The neuroprotective activity of NSP01 is based on a precise combination of three major constituents: HA and two phenolic acids, caffeic acid (CA) and ferulic acid (FA). We show that CA and FA potentiate HA-mediated neuroprotective activity. Importantly, the combination of HA with CA and FA does not potentiate the AChE inhibitory property of HA which is responsible for its adverse side effects. Collectively, these experimental findings demonstrated that NSP01, is a very promising plant extract for the prevention of Alzheimer’s disease and memory deficits.

Baricitinib in the Treatment of Patients with COVID-19: A Review of International Data and Analysis of Clinical Results in the Russian Population

The effects of baricitinib, a selective reversible inhibitor of Janus kinase 1 and 2, in the treatment of COVID-19 are associated with different aspects of pathogenesis — inhibition of viral endocytosis, reduction of excessive inflammatory response, and mitigation of vascular and pulmonary damage, which is a strong rationale for using baricitinib to treat patients with COVID-19. In the period from April to May 2020, City Clinical Hospital No. 52 obtained clinical experience of baricitinib clinical use in the therapy of 113 patients with COVID-19: 58 (51%) women and 55 (49%) men, whose average age was 57±12.6 years old. Analysis of the results of using baricitinib showed that therapy with baricitinib against the background of standard pathogenetic therapy was found to be effective in 95 (84%) patients and ineffective in 18 (16%). Significant positive changes were shown in comparison with the baseline level of the following indicators: body temperature (from 37.2±0.8˚C to 36, ±0.68˚C, P=0.000), blood oxygen saturation (from 95.5±3.0% to 96.5±2.2%, P=0.011), C-reactive protein (from 46.1±48.0 mg/L to 33.5±43.7 mg/L, P=0.010 ), National Early Warning Score (NEWS) (from 1.7±1.3 to 1.1±1.2, p=0.001). From the safety point of view, patients showed a slight decrease in the average value of the number of neutrophils — from (3.1±1.4)×109 to (3.0±2.0)×109 and lymphocytes — from (1.8±0,9)×109 to (1.7±0.9)×109, as well as minimal multidirectional changes in the mean values of transaminase activity — alanine aminotransferase changed from 33.9±23.6 U/L to 34.9±47.5 U/L, aspartate aminotransferase — from 40.6±49.0 U/L to 38.5±25.5 U/L. In general, the results obtained within the experience of the clinical use of baricitinib in 113 Russian patients with COVID-19 are consistent with the available data from foreign clinical studies and confirm the efficacy and safety of baricitinib.

Alpelisib-Induced Hyperglycemia- A Small Case Series

The phosphoinositide-3-kinase (PI3K) family consists of highly conserved enzymes that are key intermediaries in signal transduction regulating cell survival and mitogenesis. This axis has been implicated in many types of cancers. In 2019 Alpelisib (Piqray), a reversible inhibitor specific to the PI3Kα subunit, in combination with fulvestrant, was approved to treat hormone receptor positive, human epidermal growth factor receptor 2 (Her2) negative, PI3K mutated breast cancer. This approval followed SOLAR-1 trial results showing a 35% risk reduction in cancer progression or death with alpelisib-fulvestrant compared to placebo in a cohort with PI3K mutated breast cancer. PI3K also plays a critical role in the insulin signaling pathway and alpelisib has been shown to cause a dose dependent rise in plasma glucose, insulin and c-peptide. Here we present a case series of severe hyperglycemia induced by alpelisib. A 44-year-old woman with ER+/Her2(-)/PI3K positive metastatic breast cancer was started on alpelisib. Previously, HbA1C was 5.4%. Hyperglycemia developed and HbA1c rose to 9.0% within 6 months of alpelisib 300mg daily. She started metformin and empagliflozin, which she was unable to tolerate due to nausea and vomiting. Her self-monitored blood glucoses were 300-400mg/dL within hours after her morning alpelisib dose. We discontinued empagliflozin when she developed metabolic acidosis with an increased anion gap. However, prior to any dose reduction, oncology discontinued alpelisib due to evidence of cancer progression. A week later, her glucoses normalized. Second case is of a 64-year-old woman with stage IV ER+/Her2(-)/PI3K mutated breast cancer with bony metastases, who was started on alpelisib 250mg. Her prior HbA1C was 5.5%. Ten days after initiation of alpelisib, she developed grade 3 hyperglycemia (blood glucoses 200-500mg/dL). She was started on metformin 2000mg with alpelisib dosed at noon. However, she noted a marked rise in blood glucose in the afternoon, few hours following alpelisib dose. Thus, moving the alpelisib to bedtime allowed better control of glycemia by using overnight basal insulin. Similarly, a 37-year-old woman with a history of ER+/HER2(-) stage IV metastatic breast cancer to the liver, with PI3K mutation was found to have acute, severe hyperglycemia with blood glucose of 300mg/dL, despite HbA1C being only 4.7%. This was attributed to initiation of alpelisib 2 days prior to admission. Given the severity of her insulin resistance (requiring &gt; 100 units of insulin daily), alpelisib dose was reduced from 300mg to 150mg/day. On discharge, she was placed on metformin, dulaglutide, and basal and prandial insulins. Her HbA1C rose to 9.4% within 3 months of alpelisib initiation. This case series demonstrate the unique challenges in managing alpelisib induced reversible hyperglycemia.

Sildenafil 4.0—Integrated Synthetic Chemistry, Formulation and Analytical Strategies Effecting Immense Therapeutic and Societal Impact in the Fourth Industrial Era

Sildenafil is a potent selective, reversible inhibitor of phosphodiesterase type 5 (PDE5) approved for the treatment of erectile dysfunction and pulmonary arterial hypertension. Whilst twenty years have passed since its original approval by the US Food and Drug Administration (USFDA), sildenafil enters the fourth industrial era catalyzing the treatment advances against erectile dysfunction and pulmonary hypertension. The plethora of detailed clinical data accumulated and the two sildenafil analogues marketed, namely tadalafil and vardenafil, signify the relevant therapeutic and commercial achievements. The pharmacokinetic and pharmacodynamic behavior of the drug appears complex, interdependent and of critical importance whereas the treatment of special population cohorts is considered. The diversity of the available formulation strategies and their compatible administration routes, extend from tablets to bolus suspensions and from per os to intravenous, respectively, inheriting the associated strengths and weaknesses. In this comprehensive review, we attempt to elucidate the multi-disciplinary elements spanning the knowledge fields of chemical synthesis, physicochemical properties, pharmacology, clinical applications, biopharmaceutical profile, formulation approaches for different routes of administration and analytical strategies, currently employed to guide the development of sildenafil-based compositions.

Separation, identification and characterization of stress degradation products of bortezomib using HPLC and LC–MS

Bortezomib (BT) is a reversible inhibitor of proteasome which is used in the treatment of hematological cancers. To study the degradation behavior, BT was subjected to acidic, basic, neutral, photolytic, oxidative and thermal degradation conditions as per ICH guideline Q1A (R2). A gradient HPLC method has been developed for separating all the degradation products formed under various degradation conditions on Waters XBridge C18 column (150 mm × 4.6 mm × 3.5 µm) using the mobile phase composed of ammonium formate and acetonitrile. A total of six degradation products were formed in various stress conditions and these were separated identified, and characterized using high performance liquid chromatography in combination with electrospray ionization tandem mass spectrometric studies.