Current Drug Metabolism - Volume 22, Issue 12, 2021

Obesity is a major lifestyle disorder, and it is correlated with several ailments. The prevalence of obesity has elevated over the years, and it has become a global health problem. The drugs presently used for managing obesity have several side effects, such as diarrhea, leakage of oily stools, etc. On the contrary, herbal plants and natural products are considered safe for use because they have lesser side effects. New compounds isolated from medicinal plants are screened and identified to determine their effectiveness and potential in preventing abnormal weight gain. In this review, the medicinal plants and natural materials are surveyed across the literature to cover those that have the potential for managing and controlling weight gain. Furthermore, their mechanism of action, active components, and experimental methodologies are also reviewed. These herbal products can be developed as formulations for therapeutic use in obesity. The herbal plants mentioned in the review are classified based on their mechanism of action, inhibition of pancreatic lipase, and appetite suppression activities. The ability to inhibit pancreatic lipase enzyme has been used to determine the effectiveness of herbal products for the prevention of abnormal weight gain because of its action on dietary fat and suppression of appetite. This review is an attempt to summarize the herbal plants and natural products that can be used to develop formulations effective in controlling weight gain and obesity.

Neurological disorders, such as epilepsy, dementia, Parkinson’s disease and Alzheimer’s disease, occur due to disorganization of the neurons in the nervous system. Disturbances in the nervous system cause problems with the memory, senses and moods. In order to treat such disorders, scientists have been working extensively, utilizing different approaches. Nanoneurotechnology has emerged as a promising tool to manage these complicated disorders, where nanoparticles with their tunable properties such as size, shape, increased solubility, biodegradability, surface area and sharp penetration through the biological barriers, target the central nervous system. This technology targets damaged neurons without affecting healthy neurons and the Blood-Brain Barrier (BBB). In this review, we discuss neurological disorders and challenges in their diagnosis and treatment by emphasizing on the role of tailorable gold nanoparticles in therapeutic drug approaches.

Individualizing drug therapy and attaining maximum benefits of a drug devoid of adverse reactions is the benefit of personalized medicine. One of the important factors contributing to inter-individual variability is genetic polymorphism. As of now, dose titration is the only followed golden standard for implementing personalized medicine. Converting the genotypic data into an optimized dose has become easier now due to technology development. However, for many drugs, finding an individualized dose may not be successful, which further leads to a trial and error approach. These dose titration strategies are generally followed at the clinical level, and so industrial involvement and further standardizations are not feasible. On the other side, technologically driven pharmaceutical industries have multiple smart drug delivery systems which are underutilized towards personalized medicine. Transdisciplinary research with drug delivery science can additionally support the personalization by converting the traditional concept of “dose titration towards personalization” with novel “dose-cum-dosage form modification towards next-generation personalized medicine”; the latter approach is useful to overcome gene-based inter-individual variability by either blocking, to downregulate, or bypassing the biological protein generated by the polymorphic gene. This article elaborates an advanced approach to implementing personalized medicine with the support of novel drug delivery systems. As a case study, we further reviewed the genetic polymorphisms associated with tacrolimus and customized novel drug delivery systems to overcome these challenges factored towards personalized medicine for better clinical outcomes, thereby paving a new strategy for implementing personalized medicine for all other drug candidates.

Background: Carbonized herbal medicine has been used clinically for centuries in China; however, its influence on the bioavailability of compatible medicinal herbs is still unknown. Objectives: To explore the effect of a carbonized herbal medicine on the in vivo adsorption and release and absorption of other active pharmaceutical ingredients in a compound prescription. Methods: The bioavailability of carbonized Herba schizonepetae (CHS) to eight active components (epiberberine, coptisine, palmatine, berberine, phellodendrine, aesculin, aesculetin, and anemoside B4) in the aqueous extract of Pulsatillae Decoction (PDAE) was evaluated by the in vitro adsorption and release and in vivo pharmacokinetics tests. Activated carbon (AC) was used as the control. Results: In vitro experiment showed that the cumulative adsorption rates of CHS to the eight active components were 33.17%, 54.32%, 21.48%, 42.01%, 39.1%, 25.11%, 32.11%, and 23.08% which was characterized by copsitine > berberine > phellodendrine > epiperberine > aesculetin > anemoside B4 > palmatine., and they were significantly lower than those of AC. The stable release concentration in sequence was 3.23, 3.04, 3.32, 7.29, 3.17, 2.80, 1.45, and 3.81 μg/mL, which was characterized by berberine > anemoside B4 > palmatine > epiberberine > phellodendrine > coptisine > aesculin > aesculetin, and they were significantly higher than those of AC. The animal experiment indicated that the areas under the concentration-time curve (AUC0-∞) of epiberberine, berberine, aesculetin, and anemoside B4 in PDAE+CHS group were significantly higher than those in the PDAE and PDAE+AC groups, and the other four components in the PDAE+CHS group were lower than those in PDAE group but higher than those in PDAE+AC group. Conclusion: CHS could significantly improve the bioavailability of epiberberine, berberine, aesculetin, and anemoside B4 in Pulsatillae Decoction and has a sustained-release effect on berberine, aesculin, aesculetin, and anemoside B4.

Background: Herbs usually contain a mixture of biologically active constituents, which can interact with numerous prescribed drugs and alter their safety profiles. Objectives: The current investigation was aimed to evaluate the effect of commonly used herbal products including black seed (Nigella sativa), garden cress (Lepidium sativum), and fenugreek (Trigonella foenum-graecum) on the pharmacokinetics and pharmacodynamics of clopidogrel using a Wistar rat model. Methods: A GC-MS analysis revealed the presence of several phytoconstitutents (polyphenols) in the extracts of black seed, garden cress, and fenugreek. These polyphenols have the potential to interfere with clopidogrel effect. Plasma concentrations of clopidogrel were measured at different time points in the absence and presence of the concurrent use of tested herbal products and the pharmacokinetic parameters were calculated. Bleeding time was measured in various groups as a measure of the antiplatelet effect of clopidogrel. Results: Area under the plasma concentration-time curves (AUC0-∞) of clopidogrel were 35.53 ±0.89 μg/ml*h (p<0.05), 26.01 ±0.90 μg/ml*h (p>0.05) and 32.80 ±2.51 μg/ml*h (p<0.05) in the black seed, garden cress and fenugreek group, respectively, compared with that of the control group (27.02 ±0.42 μg/ml*h). Treatment with black seed also caused an increase in clopidogrel Cmax by 31.52% (p<0.05) and with fenugreek by 21.42% (p<0.05); Cmax, did not changed with garden cress treatment (6.48 ±0.15 μg/ml versus 6.12 ±0.21 μg/ml, p>0.05). The pharmacodynamic evaluation of the antiplatelet effect of clopidogrel in the presence of herbal products treatment showed a significant prolongation in the bleeding time from a control baseline by ~22-26%, and by added ~8-12% in reference to clopidogrel therapeutic effect (p<0.05). Conclusion: The concurrent use of black seed, fenugreek, or garden cress can alter the pharmacokinetics and pharmacodynamics of clopidogrel to varying degrees due to the presence of various bioactive polyphenols. This is probably due to changes in drug disposition and its antiplatelet action. Further confirmation can determine the clinical relevance of these observations and identify the exact constituents responsible for such activities.

Background: In over 300 million clinical cases, antidepressant drugs seem to provide only symptomatic relief and limited protection in life-threatening depressive events. Objectives: To compare neuronal-signaling mechanism and neuroprotective roles of Thymoquinone (TQ) suspension and its SLN (TQSLN) against standard antidepressant drug fluoxetine. Methods: This research investigated in-silico docking at NF-KB p50 active site, CLSM based gut permeation, screening of antidepressant activities and neurosignaling pathways involved. Results: As compared to fluoxetine, TQ reporteda significantly better docking score (-6.83 v/s -6.22) and a better lower free binding energy of (-34.715 Kcal/mol v/s -28.537 Kcal/mol). While poorly oral bioavailable and P-gp substrate TQ reported approximately 250% higher gut permeation if delivered as TQSLN formulation. In locomotor studies, as compared to TQS, TQSLN favored more prominent (p< 0.010) elevation in average time, horizontalactivity, average-velocity, and total-movement with reduced rest time LPS treated groups. However, in the tail suspension test, TQSLN significantly reduced immobility time (p<0.010). Similarly, In the modified force swimming test, TQSLN also significantly reduced immobility time (p<0.010), but swimming time (p<0.010) and climbing time (p<0.050) were significantly elevated. Subsequently, TQSLN reported significantly elevated neuroprotective BDNF (p<0.010) as well as hippocampal 5HT/TRP; accompanied with reduced levels of hippocampal inflammatory markers TNF-α (p<0.001) and IL-6 (p<0.010) as well as lower kynurenine and tryptophan ratio (KYN/TRP). Similarly, the hippocampal CA1 region further revealed TQSL more predominantly attenuated NF-kB nuclear translocation in the brain. Conclusion: Despite the poor bioavailability of TQ, TQSLN potentially attenuates neuroinflammatory transmitters and favors BDNF to modulate depressive neurobehavioral states.

Background: Warfarin is primarily metabolized by cytochrome P450 2C9 (CYP2C9) enzyme, which is encoded by the CYP2C9 gene. CYP2C9*2 and CYP2C9*3 variants significantly influence warfarin metabolism and subsequently the required dose of warfarin. Objectives: The current retrospective study was aimed to determine the influence of CYP2C9 variants on warfarin metabolic ratio (MR, warfarin/7-hydroxy warfarin) and warfarin maintenance therapy in 210 patients (mean age 44.6±11.6 (SD) years; male to female ratio 81:129). Methods: High-performance liquid chromatography (HPLC) with UV detector was used to measure plasma concentrations of warfarin and 7-hydroxy warfarin. Plasma samples were collected 12 h after the previous dose of warfarin was administered. CYP2C9 variants (rs1799853 and rs1057910) were identified using real-time polymerase chain reaction allele-discrimination method. Results: The mean daily maintenance dose of warfarin was 4.6±1.8 (SD) mg. The mean plasma warfarin and 7-hydroxy warfarin concentrations were 3.7±1.6 (SD) μg/mL and 1.1±0.54 (SD) μg/mL, respectively. Patients carrying other CYP2C9 variants required 39% lower warfarin maintenance dose 3.3±1.2(SD)mg than CYP2C9*1*1 carrier 4.9±1.8(SD)mg, (p<0.0001). MRs differed significantly between CYP2C9 variant carriers (8.1±5.1) and normal genotype carriers (4.8±3.9) (p<0.0001). Probit analysis identified an MR value of 7.6 as the anti-mode (sensitivity of 84% and specificity of 55%) to differentiate poor and intermediate metabolizers (carriers of any CYP2C9*2 or CYP2C9*3 variants) from normal metabolizers (CYP2C9*1*1 genotype). Conclusion: The present study results provide, insights on the effect of CYP2C9 genetic polymorphisms on inter-individual variability in warfarin metabolism and emphasizes utility of phenotyping in a setting of genotype-guided dosing of warfarin in South Indian population.

An error appeared in the graphical abstract and figure no. 1 of the article entitled “Chloro-s-triazines-toxicokinetic, toxicodynamic, human exposure, and regulatory considerations” by Khaled Abass, Olavi Pelkonen and Arja Rautio, Current Drug Metabolism 2021, 22(8), 645-656. We regret the error and apologize to readers. The original article can be found online at https://doi.org/10.2174/1389200222666210701164945