Pharmacokinetics of Dasatinib in Rats: a Potential Food-Drug Interaction with Naringenin

BACKGROUND AND OBJECTIVES

The novel tyrosine kinase inhibitor (TKI) dasatinib, a multitarget inhibitor of Bcr-Abl and Src family kinases, has been licensed for the treatment of Ph+ acute lymphoblastic leukemia and chronic myeloid leukemia. Many citrus-based foods include the flavonoid naringenin, which is commonly available. Dasatinib is a Cyp3a4, P-gp, and Bcrp1 substrate, which makes it sensitive to potential food-drug interactions. The concurrent use of naringenin may change the pharmacokinetics of dasatinib, which could result in adverse effects and toxicity. The present investigation examined the impact of naringenin on the pharmacokinetics interactions of DAS and proposes a possible interaction mechanism in Wistar rats.

METHODS

Rats were provided with a single oral dose of dasatinib (25 mg/kg) with or without naringenin pretreatment (150 mg/kg p.o. daily for 7 days, n = 6 in each group). Dasatinib was quantified in plasma by UHPLC MS/MS assay. Noncompartmental analysis was used to compute the pharmacokinetic parameters, and immunoblot was used to assess the protein expression in the hepatic and intestinal tissues.

RESULTS

Following 7 days of naringenin pretreatment, the plasma mean concentration of dasatinib was enhanced compared with without pretreatment. In rats that were pretreated with naringenin, the pharmacokinetics of the orally administered dasatinib (25 mg/kg) was shown to be significantly different from that of dasatinib given without pretreatment (p < 0.05). There was a significant enhancement in pharmacokinetic parameters elimination half-life (T1/2), time to maximum concentration ( Tmax), maximum concentration )Cmax), area under the concentration-time curve (AUC0-t), area under the moment curve (AUMC0-∞), and mean residence time (MRT) by 28.41%, 50%, 103.54%, 72.64%, 115.08%, and 15.19%, respectively (p < 0.05) and suppression in elimination rate constant (Kel), volume of distribution (Vd), and clearance (CL) by 21.09%, 31.13%, and 46.25%, respectively, in comparison with dasatinib alone group (p < 0.05). The enhancement in dasatinib bioavailability and systemic exposure resulted from the significant inhibition of Cyp3a2, Mdr1/P-gp, and Bcrp1 expression and suppression of the dasatinib hepatic and intestinal metabolism, which enhanced the rate of dasatinib absorption and decreased its elimination.

CONCLUSION

Concurrent use of naringenin-containing supplements, herbs, or foods with dasatinib may cause serious and potentially life-threatening drug interactions. Further studies are necessary to determine the clinical significance of these findings.

Herb-drug interaction: Effect of sinapic acid on the pharmacokinetics of dasatinib in rats

Dasatinib (DAS) is a narrow therapeutic index drug and novel oral multitarget inhibitor of tyrosine kinase and approved for the first-line therapy for chronic myelogenous leukemia (CML) and Philadelphia chromosome (Ph + ) acute lymphoblastic leukemia (ALL). DAS, a known potent substrate of cytochrome (CYP) 3A, P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) and is subject to auto-induction. The dietary supplementation of sinapic acid (SA) or concomitant use of SA containing herbs/foods may alter the pharmacokinetics as well as pharmacodynamics of DAS, that may probably lead to potential interactions. Protein expression in rat hepatic and intestinal tissues, as well as the in vivo pharmacokinetics of DAS and the roles of CYP3 A2 and drug transporters Pgp-MDR1 and BCPR/ABCG2, suggested a likely interaction mechanism. The single dose of DAS (25 mg/kg) was given orally to rats with or without SA pretreatment (20 mg/kg p.o. per day for 7 days, n = 6). The plasma concentration of DAS was estimated by using Ultra-High-Performance Liquid Chromatography Mass spectrometry (UHPLC-MS/MS). The in vivo pharmacokinetics and protein expression study demonstrate that SA pretreatment has potential to alter the DAS pharmacokinetics. The increase in Cmax, AUC and AUMC proposes increase in bioavailability and rate of absorption via modulation of CYP3 A2, PgP-MDR1 and BCPR/ABCG2 protein expression. Thus, the concomitant use of SA alone or with DAS may cause serious life-threatening drug interactions.

Effects of Apigenin on Pharmacokinetics of Dasatinib and Probable Interaction Mechanism

Dasatinib (DAS), a narrow-therapeutic index drug, Bcr-Abl, and Src family kinases multitarget inhibitor have been approved for chronic myelogenous leukemia (CML) and Ph-positive acute lymphocytic leukemia (Ph+ ALL). Apigenin (APG) has a long history of human usage in food, herbs, health supplements, and traditional medicine, and it poses low risk of damage. The concomitant use of APG containing herbs/foods and traditional medicine may alter the pharmacokinetics of DAS, that probably lead to possible herb-drug interactions. The pharmacokinetic interaction of APG pretreatment with DAS in rat plasma following single and co-oral dosing was successfully deliberated using the UPLC-MS/MS method. The in vivo pharmacokinetics and protein expression of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 demonstrate that APG pretreatment has potential to drastically changed the DAS pharmacokinetics where escalation in the Cmax, AUC_(0-t), AUMC_{(0-inf_obs)}, T_1/2, Tmax, and MRT and reduction in Kel, Vd, and Cl significantly in rats pretreated with APG 40 mg/kg, thus escalating systemic bioavailability and increasing the rate of absorption via modulation of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 protein expression. Therefore, the concomitant consumption of APG containing food or traditional herb with DAS may cause serious life-threatening drug interactions and more systematic clinical study on herb-drug interactions is required, as well as adequate regulation in herbal safety and efficacy.

Thymoquinone Attenuates Retinal Expression of Mediators and Markers of Neurodegeneration in a Diabetic Animal Model

BACKGROUND

Diabetic retinopathy (DR) is a slow eye disease that affects the retina due to a long-standing uncontrolled diabetes mellitus. Hyperglycemia-induced oxidative stress can lead to neuronal damage leading to DR.

OBJECTIVE

The aim of the current investigation is to assess the protective effects of thymoquinone (TQ) as a potential compound for the treatment and/or prevention of neurovascular complications of diabetes, including DR.

METHODS

Diabetes was induced in rats by the administration of streptozotocin (55 mg/kg intraperitoneally, i.p.). Subsequently, diabetic rats were treated with either TQ (2 mg/kg i.p.) or vehicle on alternate days for three weeks. A healthy control group was also run in parallel. At the end of the treatment period, animals were euthanized, and the retinas were collected and analyzed for the expression levels of brain-derived neurotrophic factor (BDNF), tyrosine hydroxylase (TH), nerve growth factor receptor (NGFR), and caspase-3 using Western blotting techniques in the retina of diabetic rats and compared with the normal control rats. In addition, dichlorofluorescein (DCF) levels in the retina were assessed as a marker of reactive oxygen species (ROS), and blood-retinal barrier breakdown (BRB) was examined for vascular permeability. The systemic effects of TQ treatments on glycemic control, kidney and liver functions were also assessed in all groups.

RESULTS

Diabetic animals treated with TQ showed improvements in the liver and kidney functions compared with control diabetic rats. Normalization in the levels of neuroprotective factors, including BDNF, TH, and NGFR, was observed in the retina of diabetic rats treated with TQ. In addition, TQ ameliorated the levels of apoptosis regulatory protein caspase-3 in the retina of diabetic rats and reduced disruption of the blood-retinal barrier, possibly through a reduction in reactive oxygen species (ROS) generation.

CONCLUSION

These findings suggest that TQ harbors a significant potential to limit the neurodegeneration and retinal damage that can be provoked by hyperglycemia in vivo.

Quality assessment of different brands of atorvastatin tablets available in Riyadh, Saudi Arabia

Background

Hypolipidemic agents have been shown to be helpful in the primary and secondary prevention of cardiovascular disease. Most often, statins are prescribed to treat hyperlipidemia. There are a number of statins available in the market today, but atorvastatin is the most widely prescribed. It is essential that the drugs should have the appropriate amount of active pharmaceutical ingredient and meet the necessary physical properties. The main purpose of the study was to evaluate the quality of different marketed brands of atorvastatin calcium tablets available in Saudi Arabia.

Methods

In this study, innovator product coded as (AS-1) and five generics brands (coded as AS-2 to AS-6) of atorvastatin tablets 20 mg available in Saudi Arabia were evaluated for in vitro dissolution test, weight variations, friability and hardness tests. The analysis of drug was carried out by “high-performance liquid chromatography” (HPLC) method using C₁₈ column (4.6 × 150 mm, 5 μm). The mobile phase was consisted of acetonitrile and HPLC water (pH 2.1, adjusted with orthophosphoric acid) in ratio of 52:48 v/v, the flow rate was 1.0 ml/min. Atorvastatin was detected at a wavelength of 254 nm.

Results

According to the results of the dissolution study, the investigated products released more than 90% of atorvastatin in 15 min. Within 60 min, the brands AS-1, AS-3, AS-5, and AS-6 depicted nearly 100% atorvastatin release, while the brand AS-2 displayed 91.69% drug release. According to our findings, the investigated atorvastatin innovator (AS-1) and generic brands such as AS-2 to AS-6 were of good pharmaceutical quality.

Conclusions

All generic brands of atorvastatin tablets available in the Saudi Arabian market met the pharmacopoeia's consistency checks such as weight variation, friability, hardness and in vitro dissolution. Hence, focusing on their in vitro release properties, it was determined that these brands could be used interchangeably.

Sinapic acid ameliorates cardiac dysfunction and cardiomyopathy by modulating NF-κB and Nrf2/HO-1 signaling pathways in streptozocin induced diabetic rats

Hyperglycemia and hyperlipidemia-arbitrated mitochondrial oxidative insult is key reason for cardiac dysfunction and cardiomyopathy. Sinapic acid (SA) is a hydroxycinnamic acid (a polyphenolic acid) present in multiple plants and possesses several pharmacological activities. In this study, we examined the cardio protective effects of SA on streptozotocin (STZ)-induced cardiac insults. STZ and both STZ induced diabetes and normal control rats were administered with 20 and 40 mg/kg SA for 12 weeks. STZ rats demonstrated hyperglycemia and hyperlipidemia. Additionally, STZ administered rats exhibited various histological changes in the cardiac muscles and significantly enhanced CK-MB and LDH. The significant enhancement of oxidative stress, inflammation, and apoptotic markers, and the capacity to curb oxidative stress was significantly abridged in the STZ induced diabetic heart. Chronic treatment with SA (20-40 mg/kg) ameliorated the increased level of glucose, lipid, and cardiac function markers and curtailed histological changes in the cardiac muscles. Chronic treatment also repressed inflammation, oxidative stress and apoptosis thereby and restoring antioxidant defenses in the myocardium of STZ induced diabetic rats. STZ induced cardiac dysfunction and cardiomyopathy by promoting inflammation and oxidative stress. Sinapic acid ameliorates cardiac dysfunction and cardiomyopathy via improvement of hyperglycemia, hyperlipidemia, inflammation, oxidative stress, and apoptosis. Thus, SA possesses possible therapeutic value for the prevention of diabetic cardiac dysfunction and cardiomyopathy via the NRF2/HO-1 and NF-κB pathways.

The potential role of thymoquinone in preventing the cardiovascular complications of COVID-19

A new virus strain detected in late 2019 and not previously described in humans is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes corona virus disease (COVID-19). While potential therapeutic approaches for COVID-19 are being investigated, significant initiatives are being made to create protective drugs and study various antiviral agents to cure the infection. However, an effective treatment strategy against COVID-19 is worrisome inadequate. The objective of the present manuscript is to discuss the potential role of thymoquinone (TQ) in preventing the cardiovascular complications of COVID-19, focusing on viral inhibition, antioxidant potential, vascular effect, and cardiac protection. The multifunctional properties of TQ could potentially synergize with the activity of current therapeutic interventions and offer a basis for managing COVID-19 disease more effectively. Even though the experimental evidence is positive, a translational application of TQ in COVID-19 is timely warranted.

Tocilizumab and Systemic Corticosteroids in the Management of Patients with COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

To date, there is no effective treatment for the new coronavirus disease (COVID-19). We aimed to systematically review the literature on the association between the combination of tocilizumab (TCZ) and systemic corticosteroid therapy (SCT) on outcomes of COVID-19 patients.

METHODS

We searched MEDLINE, Cochrane Central, and preprints, for studies in which health outcomes were compared between adults with severe COVID-19 who received TCZ and SCT and those who received standard of care without TCZ. Record screening, data extraction, and risk of bias assessment were performed in duplicate. Random effect models were used when pooling crude numbers and adjusted effect estimates of study outcomes.

RESULTS

Our search identified seventeen studies. The pooled crude mortality rate was lower in the combination arm (relative risk, RR=0.62, 95% confidence interval [CI]=0.42 - 0.91; I²=60%). The adjusted mortality rates were also lower in the combination arm (RR=0.58, 95% CI=0.42 - 0.81; I²=71%). The rate of superinfections did not differ between the two interventions.

CONCLUSIONS

The findings of this study show that combination of TCZ and SCT compared to SOC has lower mortality rates. There is an urgent need for well-designed randomized trials to assess the safety and efficacy of this combination in subjects with severe COVID-19.

Sinapic acid mitigates methotrexate-induced hepatic injuries in rats through modulation of Nrf-2/HO-1 signaling

The present research has been investigated to study the protective outcomes of sinapic acid (SA) against methotrexate (MTX) encouraged liver damage in rats by modulating the Nrf2/HO-1 and NF-κB signaling pathways. The animals were arbitrarily allocated into four groups: group I rats administered a 0.5% carboxymethyl cellulose (CMC) vehicle orally for 15 consecutive days with a single intravenous standard saline injection (0.9% NaCl) on day seven. Groups II, III, and IV were injected intraperitoneally with 20 mg MTX/kg on 7th day. Animals in group III and IV were treated orally for 14 days with 20 mg of SA/kg dissolved daily in 0.5% CMC respectively. In all experimental groups, liver function, biochemical, histopathological and molecular changes were evaluated. MTX-induced changes in liver function indices like ALT, AST, and ALP are substantially restored with SA pretreatment. Moreover, antioxidant defense mechanisms (GSH, SOD, and CAT) and oxidative/nitrostative stress (MDA and NO) and inflammatory cytokine (TNF-α, IL-β and MPO) were also substantially restored. Furthermore, the conclusions indicate that SA prevents the hepatic damage caused by MTX through apoptosis inhibition and stimulation of Nrf2/HO-1-medial antioxidant enzymes by NF-κB inhibition. Histological findings have shown that SA therapy has greatly protected liver damage caused by MTX.

Protective effect of chrysin, a flavonoid, on the genotoxic activity of carboplatin in mice

Carboplatin is amongst the most commonly used anticancer drugs for the management of several human malignancies. However, it has displayed genotoxic properties against normal cells. Evaluation of natural products for their protective effects against chemotherapeutic drug induced toxicity has been growing in recent years. A naturally occurring flavonoid, chrysin, has strong antioxidant abilities and protects against DNA impairment. This study used multiple assays to evaluate the levels of damage to DNA in normal cells and to examine any possible protective role of chrysin against such damage. Male BALB/c mice were administered chrysin orally in two doses of 20 and 40 mg/kg for 10 consecutive days and then a single injection of carboplatin [90 mg/kg body weight (b.w.)] was administered intraperitoneally to induce carboplatin toxicity. 24 h after the carboplatin injection, mice were sacrificed. DNA damage was evaluated using several genotoxicity tests (8-Hydroxydeoxy-guanosine marker, comet assay, micronucleus test, and chromosomal aberration assay) to identify diverse types of damage to the DNA. The results suggest that pretreatment with chrysin significantly decreased the level of DNA damage caused by carboplatin probably due to its potent antioxidant traits. Therefore, chrysin can be considered to be developed as a chemoprotective agent against chemotherapy associated side-effects.

Enriched pharmacokinetic behavior and antitumor efficacy of thymoquinone by liposomal delivery

Background: Thymoquinone (TQ) has potential anti-inflammatory, immunomodulatory and anticancer effects but its clinical use is limited by its low solubility, poor bioavailability and rapid clearance. Aim: To enhance systemic bioavailability and tumor-specific toxicity of TQ. Materials & methods: Cationic liposomal formulation of TQ (D1T) was prepared via ethanol injection method and their physicochemical properties, anticancer effects in orthotopic xenograft pancreatic tumor model and pharmacokinetic behavior of D1T relative to TQ were evaluated. Results: D1T showed prominent inhibition of pancreatic tumor progression, significantly greater in vivo absorption, approximately 1.5-fold higher plasma concentration, higher bioavailability, reduced volume of distribution and improved clearance relative to TQ. Conclusion: Encapsulation of TQ in cationic liposomal formulation enhanced its bioavailability and anticancer efficacy against xenograft pancreatic tumor.

Gastroprotective Effect of Sinapic Acid on Ethanol-Induced Gastric Ulcers in Rats: Involvement of Nrf2/HO-1 and NF-κB Signaling and Antiapoptotic Role

Background: In the current study, we evaluated the therapeutic potential of sinapic acid (SA) in terms of the mechanism underlying its gastroprotective action against ethanol-induced gastric ulcers in rats.

Methods: These effects were examined through gross macroscopic evaluation of the stomach cavity [gastric ulcer index (GUI)], alteration in pH, gastric juice volume, free acidity, total acidity, total gastric wall mucus, and changes in PGE2. In addition, we evaluated lipid peroxidation (malondialdehyde), antioxidant systems (catalase and glutathione), inflammatory markers [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and myeloperoxidase (MPO)], apoptotic markers (caspase-3, Bax, and Bcl-2), nuclear factor-κB [NF-κB (p65)], NO levels, and histopathological staining (H and E and PAS).

Results: In rats with ethanol-induced ulcers, pre-treatment with SA (40 mg/kg p. o.) decreased the sternness of ethanol-induced gastric mucosal injuries by decreasing the GUI, gastric juice volume, free acidity, and total acidity. In addition, the pH and total gastric mucosa were increased, together with histopathological alteration, neutrophil incursion, and increases in PGE2 and NO₂. These effects were similar to those observed for omeprazole, a standard anti-ulcer drug. SA was shown to suppress gastric inflammation through decreasing TNF-α, IL-6, and MPO, as well as curbing gastric oxidative stress through the inhibition of lipid peroxidation (MDA) and restoration of depleted glutathione and catalase activity. SA inhibited Bcl-2-associated X (Bax) and caspase-3 activity, and restored the antiapoptotic protein Bcl-2; these findings indicate the antiapoptotic potential of SA, leading to enhanced cell survival. SA also repressed NF-κB signaling and increased IκBα. Moreover, SA upregulated the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), thereby restoring depleted antioxidant defense enzymes and implicating the NRF2/HO-1 signaling pathways.

Conclusion: These results suggest that the prophylactic administration of SA (40 mg/kg) can ameliorate ethanol-induced gastric ulcers in rats primarily via the modulation of Nrf2/HO-1 and NF-κB signaling and subsequent enhancement of cell viability.

Saudi Arabia, pharmacists and COVID-19 pandemic

The latest outbreak of Covid-19 pandemic has placed a significant effect on health care system around the world. This article discusses the role of pharmacists in Saudi Arabia during the current Covid-19 pandemic. Pharmacists are an important part of everyday healthcare in Saudi Arabia. Pharmacists helped to protect the public from Covid-19 pandemic disease by participating in various initiatives including health education and promotion, medication dispensing, medication reconciliation, medication and patient counselling, training for self-management in current outbreak and emergency preparedness. Full utilization of skills of pharmacists boosted the safety response of Saudi Arabia to Covid-19 pandemic.

A Sensitive Rapid and Environmentally Friendly UHPLC Assay Method for the Determination of Thymoquinone in Plasma Samples and Its Analytical Application

A precise, swift and environmental-friendly reverse phase ultra-high performance liquid chromatographic assay for the determination of thymoquinone (TQ) in plasma samples using thymol (TM) as an internal standard was developed and validated. The method used a high strength silica C18 1.7 μm column (100 × 2.1 mm) with an isocratic mobile phase consisting of a blend of methanol and 20 mM potassium dihydrogen ortho-phosphate (90:10 v/v; pH of 4.2). The selected eluent provided a short run time (≤2 min), better peak symmetry, lower limit of quantification of 10 ng/mL and satisfactory values of other chromatographic parameters including resolution (Rs = 1), capacity factor (k = 21.5 and 14.5 for TQ and TM, respectively), selectivity (α = 1.482) and number of theoretical plates (N = 1653 and 784 for TQ and TM, respectively). The method was efficiently applied to a pharmacokinetic study of TQ following an intraperitoneal administration of 2 mg/kg in mice. The concentrations of TQ in plasma were measurable up to 12 h with Cmax of 404.08 ± 28.91 ng/mL, T1/2 of 2.31 ± 0.10 h and area under plasma concentration-time curve of 1527.00 ± 46.61 ng/mL × h.

An alternative approach to minimize the risk of coronavirus (Covid-19) and similar infections

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a new strain that was discovered in 2019 and has not been previously identified in humans. On December 31st 2019 World Health Organization (WHO) was informed of a cluster of cases with pneumonia of unknown origin from Wuhan City, Hubei province of China. The WHO announced in February 2020 that COVID-19 is the official name of the coronavirus diseases. A total of 519,899 confirmed cases with 23,592 deaths linked to this pathogen as on March 27, 2020 have been reported. Due to increasing number of infected people across the continents and huge loss to human life, the WHO has declared the novel COVID-19 outbreak a pandemic. A pandemic is defined as the "worldwide spread" of a new disease. Currently, no COVID-19 specific treatments have been approved by the United States Food and Drug Administration (US-FDA). However, the current treatment options include hydroxychloroquine, tocilizumab, remdesivir, lopinavir-ritonavir (Kaletra®), and nitazoxanide. In recent past, some natural herbal compounds have demonstrated encouraging anti-viral properties. This article attempted to summarize available information on the reported anti-viral activity of some natural products.

Effect of compromised liver function and acute kidney injury on the pharmacokinetics of thymoquinone in a rat model

The current research explored the effect of hepatic and renal dysfunctions on the pharmacokinetics of thymoquinone (TQ) in a rat model.An acute kidney injury was induced using gentamicin and a liver damage was elicited using a single dose of d-galactosamine. For the pharmacokinetic studies, TQ was administered as IV injection or and PO route to rats.The concentrations of TQ and pharmacokinetic parameters were calculated using a non-compartmental analysis. The systemic clearance (Cl) of TQ after IV dosing was slightly reduced in the liver dysfunction group compared to healthy controls (p = 0.0013). Similarly, the estimated volume of distribution at steady state (Vss) was marginally decreased (p = 0.001). However, in rats with acute kidney injury exhibited a larger Vss as opposed to normal renal function (511.28 ± 21.03 ml/kg vs. 442.25 ± 31.43 ml/kg; p = 0.0001). Whereas oral Cl and terminal volume of distribution (Vz) of TQ were reduced by ∼50% in the liver dysfunction group (p = 0.0001). These changes were associated with more systemic exposure as measured by AUC_0-∞ in rats with compromised liver functions. The estimated plasma protein binding TQ was 99.84 ± 0.03% in healthy controls, 97.05 ± 0.57% with kidney injury rats, and 95.75 ± 0.64% in liver dysfunctionThe findings of the present study suggest that liver dysfunction could potentially modify the disposition of TQ administered orally, and therefore, a smaller maintenance dose is probably required to avoid accumulation.

Sinapic Acid Ameliorates Oxidative Stress, Inflammation, and Apoptosis in Acute Doxorubicin-Induced Cardiotoxicity via the NF-κB-Mediated Pathway

In the present study, we explored SA's activity against DOX-induced cardiotoxicity and revealed its underlying mechanisms. Male Wistar rats (weight, 190-210g; n = 6) were randomly divided into four groups: group I, normal control; group II, DOX 15 mg/kg via intraperitoneal (ip) route; group III, administered DOX+SA 20 mg/kg; and group IV, administered DOX+captopril (CAP 30 mg/kg). SA and CAP were administered orally for seven days, and DOX (15 mg/kg) was injected intraperitoneally an hour before SA treatment on the fifth day. Forty-eight hours after DOX administration, animals were anesthetized and sacrificed for molecular and histology experiments. SA significantly mitigated the myocardial effects of DOX, and following daily administration, it reduced serum levels of lactate dehydrogenase (LDH) and creatine kinase isoenzyme-MB to near normal values. Levels of oxidative stress markers, glutathione-peroxidase, superoxide dismutase, and catalase, in the cardiac tissue were significantly increased, whereas malondialdehyde levels decreased after SA treatment in DOX-administered rats. Furthermore, DOX caused an inflammatory reaction by elevating the levels of proinflammatory cytokines, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and endothelin- (ET-) 1, as well as nuclear factor kappa-B (NF-κB) expression. Daily administration of SA significantly repressed TNF-α, IL-1β, ET-1, and NF-κB levels. caspase-3 and Bax expression, bcl-2-like protein and caspase-3 activities and levels. Overall, we found that SA could inhibit DOX-induced cardiotoxicity by inhibiting oxidative stress, inflammation, and apoptotic damage.

Thymoquinone treatment modulates the Nrf2/HO-1 signaling pathway and abrogates the inflammatory response in an animal model of lung fibrosis

The present study investigates the therapeutic potential of thymoquinone (TQ) in bleomycin-induced lung fibrosis (BMILF) and elucidates the target-signaling pathway for its effect. Lung fibrosis was induced in rats by a single intra-tracheal instillation of bleomycin (BM) (6.5 U/kg) followed by thymoquinone treatment (10 and 20 mg/kg p.o.) for 28 days. Control rats received saline instead of TQ. Changes in body weight, inflammatory cells count, cytokines levels, and biochemical parameters of the broncho-alveolar lavage fluid (BALF) were recorded. In addition, a histopathology examination and western blotting were performed on lung tissues. BM administration resulted in a significant weight loss, which was ameliorated by TQ treatment. BMILF was associated with a reduction in the antioxidant mechanisms and increased lipid peroxidation. Furthermore, elevated levels of inflammatory cytokines, MMP-7 expression, apoptotic markers (caspase 3, Bax, and Bcl-2), and fibrotic changes including TGF-β and hydroxyproline levels in lung tissues were evident. These abnormalities were diminished with TQ treatment. Likewise, altered total and differential cell count in BALF was significantly improved in rats treated with TQ. TQ also produced a dose-dependent reduction in the expressions of Nrf2, Ho-1 and TGF-β. These results propose that the Nrf2/Ho-1 signaling pathway is a principal target for TQ protective effect against BMILF in rats. Furthermore, TQ decreases inflammatory oxidative stress possibly through the modulation of nuclear factor Kappa-B (NF-κB) and thereby minimization of collagen deposition in the lung. Therefore, TQ can be developed as a potential therapeutic modularity in BMILF for human use.

Gender effect on the pharmacokinetics of thymoquinone: Preclinical investigation and in silico modeling in male and female rats

Thymoquinone is the most biologically active constituent of Nigella sativa (black seed). A monoterpene compound chemically known as 2-methyl-5-isopropyl-1, 4-quinone. In this study, the gender-dependent pharmacokinetic behavior of thymoquinone in rats was investigated. Thymoquinone was administered orally (20 mg/kg) and intravenously (5 mg/kg) to male and female rats and blood samples were collected at specific time points. Plasma concentration-time curves were plotted and pharmacokinetic parameters were determined using the non-compartmental analysis. In addition, simulations of steady state concentrations of thymoquinone in male and female rats were performed using GastroPlus PK software. After oral administration, the maximum plasma concentration (C_max) of thymoquinone was 4.52 ± 0.092 μg/ml in male rats and 5.22 ± 0.154 μg/ml in female rats (p = 0.002). Similarly, after intravenous administration, the C_max was 8.36 ± 0.132 μg/ml in males and 9.51 ± 0.158 μg/ml in females (p = 0.550). The area under the plasma concentration-time curve (AUC)_0-∞ following oral dosing was 47.38 ± 0.821 μg/ml·h in females and 43.63 ± 0.953 μg/ml·h in males (p = 0.014). Pharmacokinetics and plasma concentration vs. time profiles for multiple oral doses of thymoquinone in rats were predicted using a simulation model to compare the simulation results with the experimental plasma pharmacokinetic data. The differences observed in thymoquinone pharmacokinetics between male and female rats after a single dose were not evident for the simulated steady-state parameters. The findings suggest that the gender difference does not seem to play a significant role in thymoquinone disposition at steady state.

Optimization of the extraction condition for benzyl isothiocyanate contents in Salvadora persica roots "Siwak"

Benzyl isothocyanate is the major active antibacterial metabolite in Salvadora persica roots "Siwak" beside two minor isothiocyanate derivatives namely; 3-methoxy benzyl isothiocyanate and 3-hydroxy benzyl isothiocyanate. The extraction condition effect on the amount of benzyl isothiocyanate was explored in detailed study. Both cold and hot extraction with different solvents was applied. The amount of benzyl isothiocyanate was estimated using HPLC and HPTLC. The results indicated that cold extraction of the fresh samples with chloroform offers the maximum amount of benzyl isothiocyanate. Drying process leads to great loss of the active component of Siwak.

Evaluation of the in vivo genotoxicity of liposomal formulation for delivering anticancer estrogenic derivative (ESC8) in a mouse model

The genotoxic potential of glucocorticoid receptor (GR)-targeted liposomal formulations of the anticancer drug molecule ESC8 was studied in vivo. A methodical literature review discovered no previous studies on the genotoxicity of ESC8. Genotoxicity was assessed in both male and female mice by various assay systems, such as comet assay, chromosomal aberrations and micronuclei assay, which detect different abnormalities. Eleven groups of male mice and eleven groups of female mice, containing six animals per group, were used in the present study: group I served as vehicle control; group II received the positive control (cyclophosphamide 40 mg/kg; CYP); and animals in group III to XI received free drug (ESC8), DX liposome and drug-associated DX liposomal formulation (DXE), respectively, dissolved in 5% solution of glucose at a drug-dose of 1.83, 3.67 and 7.34 mg/kg, respectively. Same drug treatments were followed for the female mice groups. The obtained data revealed the safety of DXE, which did not show substantial genotoxic effects at different dose levels. In contrast, the positive control, CYP, exhibited highly substantial irregular cytogenetic variations in comparison with the control group in different assays.

Directly compressed rosuvastatin calcium tablets that offer hydrotropic and micellar solubilization for improved dissolution rate and extent of drug release

The objective was to use caffeine and Soluplus® to improve the dissolution rate and to maintain a concentration of BCS Class II rosuvastatin calcium that exceeds its solubility. Caffeine and Soluplus® together substantially improved the dissolution rate and the extent of rosuvastatin release. Formulations for direct compression tablets included Formulation F1, a control with drug but with neither caffeine nor Soluplus® present; F2 with drug-caffeine complex; F3 with drug and Soluplus® and F4 with drug-caffeine complex and Soluplus®. Each formulation blend provided satisfactory flow properties. Tablets were comparable in mass, hardness and friability. A marked decrease in disintegration time occurred when the hydrotropic or micellar agent was included in the formulation. Assay (98–100%) and content uniformity (99–100%) results met requirements. Release studies in pH 1.2, 6.6, and 6.8 buffers revealed the superiority of F4. At 45 min sampling time, F3 and F4 tablets each provided a cumulative drug release greater than 70% in each medium. F2 tablets exhibited compliance to official standards in pH 6.6 and 6.8 buffers but not in pH 1.2 buffer, whereas tablets based on F1 failed in each medium. Two-factor ANOVA of the release data revealed a statistical difference across the four formulations in each release medium. Pairwise comparison of release profiles demonstrated that, of the four formulations, F4 provided the most effectively enhanced dissolution rate, improvement to the extent of drug release and support of a concentration higher than the solubility of rosuvastatin calcium.

Effects of sinapic acid on hepatic cytochrome P450 3A2, 2C11, and intestinal P-glycoprotein on the pharmacokinetics of oral carbamazepine in rats: Potential food/herb-drug interaction

Dietary supplements, herbal medicines, and other foods may affect the pharmacokinetics and/or pharmacodynamics of carbamazepine (CBZ), which may possibly lead to potential drug-drug/herb-drug interactions, as CBZ has a narrow therapeutic window. Sinapic acid (SA) is a bioactive phytoconstituent used as a dietary supplement for the treatment of epilepsy. This study determined the effects of SA on the pharmacokinetics of CBZ and proposed a possible interaction mechanism in twenty-four male wistar rats (180-210 g). A single CBZ dose (80 mg/kg) was administered orally to rats with or without SA pretreatment (20 mg/kg p.o. per day for 7 days, n = 6). The CBZ concentration in plasma samples was determined by using a sensitive reversed-phase high-performance liquid chromatography assay. The pharmacokinetic parameters were calculated by using non-compartmental analysis. Significance was determined through Dunnett's multiple comparison test or one-way analysis of variance as appropriate; p < 0.05 were considered significant. The change in the pharmacokinetic parameters (C_max, T_max, AUC_0-t, AUC_0-∞, T_½, and k_el) of CBZ was evaluated after the administration of CBZ alone or after CBZ co-administration with SA pretreatment. The plasma concentration of CBZ was higher after SA pretreatment than that without pretreatment. The pharmacokinetics of orally administered CBZ were found to be significantly altered (p < 0.05) in rats pretreated with SA compared to those in rats administered CBZ alone. The increases in the C_max, AUC_0-t, T_1/2, and MRT of CBZ were 29.79%, 57.18%, 77.18%, and 58.31%, respectively, whereas the k_el and apparent oral CL/F were significantly reduced (p < 0.05) in rats pretreated with SA compared to those in rats not pretreated with SA (43.87% and 42.50%, respectively). However, no significant change was observed in the T_max of CBZ in rats pretreated with SA compared to that in rats that did not receive pretreatment. The enhancement in Cmax, AUC_0-t, T_1/2, and MRT and the reduction in K_el and CL/F values resulted from the significant inhibition of CYP3 A2, the CYP2C11-mediated metabolism of CBZ in the liver, and the inhibition of intestinal P-glycoprotein/MDR1, which enhanced the rate of CBZ absorption. Further studies are required to determine the clinical relevance of these observations.

Effect of sinapic acid on aripiprazole pharmacokinetics in rats: Possible food drug interaction

Dietary supplements and foods can interact with various drugs, leading to possible clinical concerns. This study aimed to investigate the effect of orally administered sinapic acid (SA) on the pharmacokinetics of aripiprazole (APZ) in rats and its possible modulatory effects on hepatic cytochrome P450 (CYP3A2 and CYP2D6) expression in the liver tissues. Single dose and multiple dose parallel groups of wistar rats were categorized into six groups (n = 6 each) which abstained from food for 12 h prior to the experiment, while water was allowed ad libitum. The investigation was carried out for single dose: Group I was treated with normal saline orally for 15 days (normal control). Group II was administered normal saline orally for 15 days and received APZ (3 mg/kg p.o.) on day 15. Group III received SA (20 mg/kg p.o.) for 15 days and received APZ (3 mg/kg p.o.) on day 15. Group IV was treated with SA (20 mg/kg p.o.) for 15 days. For the multiple dose study, Group I was treated with normal saline orally for 15 days (normal control); Group II received APZ (3 mg/kg p.o.) daily for 15 days; Group III was administered with SA (20 mg/kg p.o.) and APZ (3 mg/kg p.o.) for 15 days and Group IV received SA (20 mg/kg p.o.) for 15 days. The group I and IV were kept common in single and multiple dose groups. After last APZ dose, plasma samples were collected and APZ concentrations were determined using an UPLC-MS/MS technique. The pharmacokinetic parameters were calculated using a non-compartmental analysis. The concomitant administration of APZ with SA (as single or multiple dose) resulted in an increase in APZ absorption and a decrease on its systemic clearance. This was associated with a reduction in CYP3A2 and CYP2D6 protein expressions by 33-43% and -71-68% after the single and multiple co-administration, which are two enzymes responsible of the metabolism of APZ. Therefore, a reduction in the metabolic clearance appears to be the mechanism underlying the drug interaction of dietary supplement containing SA with APZ. Therefore, the concomitant administration of SA and APZ should be carefully viewed. Further investigations are required to assess the clinical significance of such observations in humans.

Inhibitory effects of Lepidium sativum polysaccharide extracts on TNF-α production in Escherichia coli-stimulated mouse

The present study was designed to study the quantitative effects of extraction time, temperature and solvent to sample ratio on the yield of Lepidium sativum polysaccharides (LSP) using a Box-Behnken design. The activities of the optimized LSP extract were then tested in an in vivo experimental system of Escherichia coli (E. coli)-induced endotoxin shock. The optimal polysaccharide extraction conditions were established by the equation of regression and evaluation of the response surface contour plots: extraction time 5.2 h; temperature 95 °C and ratio of water to raw material 31.89 mL/g. Subsequently, an in vivo endotoxin shock was induced in mice with a single E. coli i.p. injection. Septic mice showed a substantial raise in the levels of tumor necrosis factor alpha (TNF-α) in plasma, whereas mice treated with LSP after E. coli injection showed considerable lower plasma levels of TNF-α (P < 0.05). These results suggest that LSP have beneficial effects when administered to mice with endotoxin shock by diminishing the pro-inflammatory response. The systemic activity of LSP indicated that the extract has a significant inhibitory effect against E. coli-induced inflammation by reducing the circulating levels of TNF-α. Further studies are warranted to explore the clinical implications of such observations.

Thymoquinone reduces mortality and suppresses early acute inflammatory markers of sepsis in a mouse model

BACKGROUND

Sepsis is a severe systemic condition caused by an excessive inflammatory response to microbial infections, which often results in high mortality.

AIMS

In the present study, the therapeutic effects of thymoquinone were investigated for Gram-negative bacteria-induced sepsis in mice.

METHODS

Thymoquinone was administered as 1or 2?mg/kg intraperitoneally 2?h after Escherichia coli (E. coli) challenge. Animal morality was assessed up to 96?h post infection and inflammatory proteins levels were measured 6?h after thymoquinone treatment in various groups using enzyme-linked immunosorbent assay (ELISA) techniques.

KEY FINDINGS

The E. coli inoculation markedly increased the level of plasma cytokines, including tumor necrosis factor (TNF)-?, interleukin (IL)-1, IL-2, IL-6 and IL-10. In addition, the levels of selected early sepsis biomarkers such as CRP, VEGF and ESM-1 were amplified in the septic group. Treatment with thymoquinone significantly downregulated the circulating concentrations of the inflammatory proteins (p?<?0.05). In addition, ?75% of mice in the thymoquinone (1?mg/kg) group survived at 96h of observation compared with ?8% of the untreated group (p?=?0.0016).

SIGNIFICANCE

The present results indicate that thymoquinone suppresses acute inflammatory responses induced by sepsis including early stage biomarkers and reduces sepsis-related mortality. These findings suggest that thymoquinone could be of a potential therapeutic value in the management of sepsis.

Effects of Paeonia emodi on hepatic cytochrome P450 (CYP3A2 and CYP2C11) expression and pharmacokinetics of carbamazepine in rats

Herbal medicines, dietary supplements, and other foods may pharmacokinetically and/or pharmacodynamically interact with carbamazepine (CBZ), which could lead to potential clinical consequences. Paeonia emodi (PE) is one of the herbs used as complementary therapy in the treatment of epileptic patients in some cultures, and may also be co-administered with CBZ. This study evaluates the effects of PE on the pharmacokinetics of CBZ and determines a possible mechanism of interaction. Rats were administered vehicle saline or PE (200mg/kg, p.o. daily for 7days), then administered a single CBZ dose (80mg/kg, p.o.) on day 7. Plasma samples were analyzed for CBZ concentrations using a sensitive reversed-phase high-performance liquid chromatography (RP-HPLC) assay. Pharmacokinetic parameters were calculated using non-compartmental analysis. The co-administration of PE with CBZ resulted in increased plasma maximum concentration (C_max), area under the curve (AUC_0-∞), and half-life (T_½), by 14.61%, 48.12%, and 43.72%, respectively. The calculated oral clearance (CL/F) was reduced by 33.54%, while the volume of distribution (V_ss) was unaffected. The PE extract also showed a significant potential to reduce CYP3A and CYP2C protein expression by approximately 50%. Therefore, a reduction in the metabolic capacity responsible for CBZ clearance appears to be the mechanism behind this herb-drug interaction. Consequently, the concomitant administration of PE and CBZ should be viewed cautiously. Further studies are needed to determine the clinical relevance of these observations.

GC-MS-based Metabolomic Profiling of Thymoquinone in Streptozotocin-induced Diabetic Nephropathy in Rats

*Diabetic nephropathy is a common complication of diabetes mellitus and one of the major etiologies of end-stage renal disease. Specific therapeutic interventions are necessary to treat such complications. The present study was designed to investigate the metabolomic changes induced by thymoquinone for the treatment of diabetic nephropathy, using a rodent model. Rats were divided into three different groups (n = 6 each): control, diabetic, and thymoquinone- treated diabetic groups. Metabolites in serum samples were analyzed via gas chromatography-mass spectrometry. Multiple changes were observed, including those related to the metabolism of amino acids and fatty acids. The correlation analysis suggested that treatment with thymoquinone led to the reversal of diabetic nephropathy that was associated with modulations in the metabolism and proteolysis of amino acids, fatty acids, glycerol phospholipids, and organic acids. In addition, we explored the mechanisms linking the metabolic profiling of diabetic nephropathy, with a particular emphasis on the potential roles of increased reactive oxygen species production and mitochondrial dysfunctions. Our findings demonstrated that metabolomic profiling provided significant insights-into the basic mechanisms of diabetic nephropathy and the therapeutic effects of thymoquinone.

GC-MS-based Metabolomic Profiling of Thymoquinone in Streptozotocin-induced Diabetic Nephropathy in Rats

Diabetic nephropathy is a common complication of diabetes mellitus and one of the major etiologies of end-stage renal disease. Specific therapeutic interventions are necessary to treat such complications. The present study was designed to investigate the metabolomic changes induced by thymoquinone for the treatment of diabetic nephropathy, using a rodent model. Rats were divided into three different groups (n = 6 each): control, diabetic, and thymoquinone-treated diabetic groups. Metabolites in serum samples were analyzed via gas chromatography-mass spectrometry. Multiple changes were observed, including those related to the metabolism of amino acids and fatty acids. The correlation analysis suggested that treatment with thymoquinone led to the reversal of diabetic nephropathy that was associated with modulations in the metabolism and proteolysis of amino acids, fatty acids, glycerol phospholipids, and organic acids. In addition, we explored the mechanisms linking the metabolic profiling of diabetic nephropathy, with a particular emphasis on the potential roles of increased reactive oxygen species production and mitochondrial dysfunctions. Our findings demonstrated that metabolomic profiling provided significant insights into the basic mechanisms of diabetic nephropathy and the therapeutic effects of thymoquinone.

Sinapic acid ameliorate cadmium-induced nephrotoxicity: In vivo possible involvement of oxidative stress, apoptosis, and inflammation via NF-κB downregulation

Cadmium (CD), an environmental and industrial pollutant, generates reactive oxygen species (ROS) and NOS responsible for oxidative and nitrosative stress that can lead to nephrotoxic injury, including proximal tubule and glomerulus dysfunction. Sinapic acid (SA) has been found to possess potent antioxidant and anti-inflammatory effects in vitro and in vivo. We aimed to examine the nephroprotective, anti-oxidant, anti-inflammatory, and anti-apoptotic effects of SA against CD-induced nephrotoxicity and its underlying mechanism. Kidney functional markers (serum urea, uric acid, creatinine, LDH, and calcium) and histopathological examinations of the kidney were used to evaluate CD-induced nephrotoxicity. Oxidative stress markers (lipid peroxidation and total protein), renal nitrosative stress (nitric oxide), antioxidant enzymes (catalase and NP-SH), inflammation markers (NF-κB [p65], TNF-α, IL-6, and myeloperoxidase [MPO]), and apoptotic markers (caspase 3, Bax, and Bcl-2) were also assessed. SA (10 and 20mg/kg) pretreatment restored kidney function, upregulated antioxidant levels, and prevented the elevation of lipid peroxidation and nitric oxide levels, significantly reducing oxidative and nitrosative stress. CD upregulated renal cytokine levels (TNF-α, IL-6), nuclear NF-κB (p65) expression, NF-κB-DNA-binding activity, and MPO activity, which were significantly downregulated upon SA pretreatment. Furthermore, SA treatment prevented the upregulation of caspase 3 and Bax protein expression and upregulated Bcl-2 protein expression. SA pretreatment also alleviated the magnitude of histological injuries and reduced neutrophil infiltration in renal tubules. We conclude that the nephroprotective potential of SA in CD-induced nephrotoxicity might be due to its antioxidant, anti-inflammatory, and anti-apoptotic potential via downregulation of oxidative/nitrosative stress, inflammation, and apoptosis in the kidney.

Oral bioavailability enhancement and hepatoprotective effects of thymoquinone by self-nanoemulsifying drug delivery system

Thymoquinone (TQ) is a poorly water soluble bioactive compound which shows poor oral bioavailability upon oral administration. Due to poor aqueous solubility and bioavailability of TQ, various self-nanoemulsifying drug delivery systems (SNEDDS) of TQ were developed and evaluated for enhancement of its hepatoprotective effects and oral bioavailability. Hepatoprotective and pharmacokinetic studies of TQ suspension and TQ-SNEDDS were carried out in rat models. Different SNEDDS formulations of TQ were developed and thermodynamically stable TQ-SNEDDS were characterized for physicochemical parameters and evaluated for drug release studies via dialysis membrane. Optimized SNEDDS formulation of TQ was selected for further evaluation of in vivo evaluation. In vivo hepatoprotective investigations showed significant hepatoprotective effects for optimized TQ-SNEDDS in comparison with TQ suspension. The oral administration of optimized SNEDDS showed significant improvement in in vivo absorption of TQ in comparison with TQ suspension. The relatively bioavailability of TQ was enhanced 3.87-fold by optimized SNEDDS in comparison with TQ suspension. The results of this research work indicated the potential of SNEDDS in enhancing relative bioavailability and therapeutic effects of natural bioactive compounds such as TQ.

Hepatoprotective activity of Lepidium sativum seeds against D-galactosamine/lipopolysaccharide induced hepatotoxicity in animal model

BACKGROUND

Fulminant hepatic failure (FHF) is clinical syndrome with very poor prognosis and high mortality there is urgent need for the development of safe and non-toxic hepatoprotective agents for the adequate management of hepatitis. Hepatoprotective effect of the Lepidium sativum ethanolic extract (LSEE) was assessed by D-galactosamine-induced/lipopolysaccharide (400 mg/kg and 30 μg/kg) liver damage model in rats.

METHODS

Hepatoprotective activity of LSEE (150 and 300 mg/kg) and silymarin on D-GalN/LPS induced FHF in rat was assessed using several liver function enzyme parameters. Antioxidant properties as antioxidant stress enzymes were assessed in hepatic Liver as well as mRNA expression of cytokines genes such as TNF-α, IL-6, and IL-10 and stress related genes iNOS and HO-1 were determined by RT-PCR. Protein expression of apoptotic genes were evaluated through western blot. MPO and NF-κB DNA-binding activity was analyzed by ELISA. The magnitude of hepatic impairment was investigated through histopathological evaluation.

RESULTS

Marked amelioration of hepatic injuries by attenuation of serum and lipid peroxidation has been observed as comparable with silymarin (25 mg/kg p.o). D-GalN/LPS induced significant decrease in oxidative stress markers protein level, and albumin. LSEE significantly down-regulated the D-GalN/LPS induced pro-inflammatory cytokines TNFα and IL-6 mRNA expression in dose dependent fashion about 0.47 and 0.26 fold and up-regulates the IL-10 by 1.9 and 2.8 fold, respectively. While encourages hepatoprotective activity by down-regulating mRNA expression of iNOS and HO-1. MPO activity and NF-κB DNA-binding effect significantly increased and was mitigated by LSEE in a dose-dependent style as paralleled with silymarin.

CONCLUSION

Our data suggests that pretreatment of LSEE down regulates the caspase 3 and up-regulates the BCl₂ protein expression. The above findings revealed that Lepidium sativum has significant hepatoprotective activity.

Antioxidant Potential and In Situ Analysis of Major and Trace Element Determination of Ood-saleeb, a Known Unani Herbal Medicine by ICP-MS

The intention of the present research work was to investigate the antioxidant activity and trace element analysis of Ood-saleeb, a known herbal medicine. Preliminary screening of phytochemicals showed that the extract of Ood-saleeb had flavonoids and phenolics. The significant activities in all antioxidant assays were observed in the extract of Ood-saleeb in comparison with the standard antioxidant with respect to dose of Ood-saleeb. Incredible activities to scavenge reactive oxygen species were also observed by the extract of Ood-saleeb. The IC50 values of all factors were determined using ascorbic acid as a standard. The inductive coupled plasma-mass spectroscopy (ICP-MS) was employed for the estimation of trace elements in Ood-saleeb extract. The concentrations of up to 18 elements were detected successfully. Silicon was found in high concentration (85.3 μg/g) while lithium was in low concentration (3 ng/g). The trace elements in the sample were found at different percentage levels which play a key role in the treatment of diseases.

Endothelium-Dependent Contractions of Isolated Arteries to Thymoquinone Require Biased Activity of Soluble Guanylyl Cyclase with Subsequent Cyclic IMP Production

Preliminary experiments on isolated rat arteries demonstrated that thymoquinone, a compound widely used for its antioxidant properties and believed to facilitate endothelium-dependent relaxations, as a matter of fact caused endothelium-dependent contractions. The present experiments were designed to determine the mechanisms underlying this unexpected response. Isometric tension was measured in rings (with and without endothelium) of rat mesenteric arteries and aortae and of porcine coronary arteries. Precontracted preparations were exposed to increasing concentrations of thymoquinone, which caused concentration-dependent, sustained further increases in tension (augmentations) that were prevented by endothelium removal, Nω-nitro-L-arginine methyl ester [L-NAME; nitric oxide (NO) synthase inhibitor], and 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; soluble guanylyl cyclase [sGC] inhibitor). In L-NAME-treated rings, the NO-donor diethylenetriamine NONOate restored the thymoquinone-induced augmentations; 5-[1-(phenylmethyl)-1H-indazol-3-yl]-2-furanmethanol (sGC activator) and cyclic IMP (cIMP) caused similar restorations. By contrast, in ODQ-treated preparations, the cell-permeable cGMP analog did not restore the augmentation by thymoquinone. The compound augmented the content (measured with ultra-high performance liquid chromatography-tandem mass spectrometry) of cIMP, but not that of cGMP; these increases in cIMP content were prevented by endothelium removal, L-NAME, and ODQ. The augmentation of contractions caused by thymoquinone was prevented in porcine arteries, but not in rat arteries, by 1-(5-isoquinolinylsulfonyl)homopiperazine dihydrochloride and trans-4-[(1R)-1-aminoethyl]-N-4-pyridinylcyclohexanecarboxamide dihydrochloride (Rho-kinase inhibitors); in the latter, but not in the former, it was reduced by 3,5-dichloro-N-[[(1α,5α,6-exo,6α)-3-(3,3-dimethylbutyl)-3-azabicyclo[3.1.0]hex-6-yl]methyl]-benzamide hydrochloride (T-type calcium channel inhibitor), demonstrating species/vascular bed differences in the impact of cIMP on calcium handling. Thymoquinone is the first pharmacological agent that causes endothelium-dependent augmentation of contractions of isolated arteries, which requires endothelium-derived NO and biased sGC activation, resulting in the augmented production of cIMP favoring the contractile process.

Quantification of lipid modified estrogenic derivative (ESC8) in rat plasma by LC-MS: application to a pharmacokinetic study

A lipid-conjugated, estrogenic derivative molecule, ESC8, compared with other estrogenic molecules, encourages cell death in both ER-positive and ER-negative breast cancer cells. A rapid and highly sensitive assay method has been developed and validated for the estimation of a ESC8 in rat plasma using liquid chromatography coupled with mass spectrometry under positive-ion mode with electrospray ionization. The sample process includes using methanol for precipitation of ESC8 and dextromethorphan (internal standard, IS) from plasma. Chromatographic separation was achieved with methanol-water-formic acid (70:30:0.1% v/v/v) pumped at a flow rate of 0.3mL/min and a C₁₈ column (50 × 2.1 mm i.d., 1.7 μm particle size) with a total run time of 5 min. The m/z ions monitored were 568.5 and 272.1 for ESC8 and IS, respectively. The lower limit of quantitation achieved was 1.08 ng/mL and linearity was observed from 5 to 500 ng/mL. The intra- and inter-day precisions were <4%. The proposed method was successfully applied to a preliminary pharmacokinetic study of ESC8 liposomal formulation following an intraperitoneal administration of 3.67 mg/kg in rats. The concentrations of ESC8 in plasma were quantifiable up to 36 h. The peak concentration of ESC8 was found to be 110.72 ng/mL, the area under the concentration-time curve was 1625.23ng/mL h and the half-life was 11.72 h.

Prevalence of UDP-glucuronosyltransferase polymorphisms (UGT1A6∗2, 1A7∗12, 1A8∗3, 1A9∗3, 2B7∗2, and 2B15∗2) in a Saudi population

Glucuronidation is an important phase II pathway responsible for many endogenous substances and drug metabolism. The present work evaluated allele frequencies of certain UDP-glucuronosyl-transferases (UGT 1A6∗2, A7∗12, A8∗3, A9∗3, 2B7∗2, and 2B15∗2) in Saudi Arabians that could provide essential ethnic information. Blood samples from 192 healthy unrelated Saudi males of various geographic regions were collected. Genomic DNA was isolated and genotyping of various UGTs was carried out using polymerase chain reaction (PCR) followed by direct sequencing. For UGT1A6∗2 A/G genotype, the most common variant was the homozygous repeat (AA) and the most common allele was (A) with a frequency of 46.5% and 67.3%, respectively. Similarly, the most common variant for UGT1A7∗12 T/C genotype was the heterozygous repeat (TC) with a frequency of 78.7% while the mutant allele (C) was present in 60.6% of the study population. Both UGT1A8∗3 (G/A) and UGT1A9∗3 (T/C) showed only a wild homozygous pattern in all screened subjects. For UGT2B7∗2, the heterozygous repeat (TC) was found with a frequency of 57.3% and the alleles (A) showed a frequency of 50.8%. In contrast, for UGT2B15∗2 (G253T), the heterozygous repeat (TG) presented 62.3% of the subjects where the most common allele (G) was with a frequency of 66.2%. In conclusion, our data indicate that Saudis harbor some important UGT mutations known to affect enzyme activity. Additional studies are therefore, warranted to assess the clinical implications of these gene polymorphisms in this ethnic group.

Development of Liposomal Formulation for Delivering Anticancer Drug to Breast Cancer Stem-Cell-Like Cells and its Pharmacokinetics in an Animal Model

The objective of the present study is to develop a liposomal formulation for delivering anticancer drug to breast cancer stem-cell-like cells, ANV-1, and evaluate its pharmacokinetics in an animal model. The anticancer drug ESC8 was used in dexamethasone (Dex)-associated liposome (DX) to form ESC8-entrapped liposome named DXE. ANV-1 cells showed high-level expression of NRP-1. To enhance tumor regression, we additionally adapted to codeliver the NRP-1 shRNA-encoded plasmid using the established DXE liposome. In vivo efficacy of DXE-NRP-1 was carried out in mice bearing ANV-1 cells as xenograft tumors and the extent of tumor growth inhibition was evaluated by tumor-size measurement. A significant difference in tumor volume started to reveal between DXE-NRP-1 group and DXE-Control group. DXE-NRP-1 group showed ∼4 folds and ∼2.5 folds smaller tumor volume than exhibited by untreated and DXE-Control-treated groups, respectively. DXE disposition was evaluated in Sprague-Dawley rats following an intraperitoneal dose (3.67 mg/kg of ESC8 in DXE). The plasma concentrations of ESC8 in the DXE formulation were measured by liquid chromatography mass spectrometry and pharmacokinetic parameters were determined using a noncompartmental analysis. ESC8 had a half-life of 11.01 ± 0.29 h, clearance of 2.10 ± 3.63 L/kg/h, and volume of distribution of 33.42 ± 0.83 L/kg. This suggests that the DXE liposome formulation could be administered once or twice daily for therapeutic efficacy. In overall, we developed a potent liposomal formulation with favorable pharmacokinetic and tumor regressing profile that could sensitize and kill highly aggressive and drug-resistive cancer stem-cell-like cells.

Effect of Trigonella foenum-graecum L. on Metabolic Activity of CYP2D6 and CYP3A4

BACKGROUND

The present study investigated the effect of fenugreek seeds powder and its alcoholic extract on metabolic activity of drug-metabolizing enzymes CYP2D6 and CYP3A4.

MATERIALS AND METHODS

Dextromethorphan (DEX) was used as a probe for measuring metabolic activity, based on its CYP2D6- and CYP3A4-mediated metabolism to dextrorphan (DOR) and 3-methoxymorphinan (3-MM), respectively. For the in vitro investigations, DEX (25µM) was incubated with human liver microsomes and NADPH and tested with and without the fenugreek extract. For the in vivo study, phase I, 6 subjects received a single dose of DEX (30 mg); in phase II, after washout period, the fenugreek seeds powder was administered for 1 week and DEX was administered with its last dose.

RESULTS

In vitro, fenugreek extract inhibits CYP2D6-mediated O-demethylation of DEX. Higher concentrations (50 and 100µg/ml) of extract inhibit CYP2D6 and CYP3A4 activity. In vivo results indicated that fenugreek does not significantly inhibit CYP2D6 and CYP3A4 metabolic activity. There was no significant change in the levels of DEX metabolites (DOR 12% and 3-MM 9%) excreted in urine and their urine metabolic ratios (P values: 0.257 and 0.333 DEX/DOR and DEX/3-MM, respectively).

CONCLUSION

In vitro and in vivo observations suggested that fenugreek may not have substantial effect on the metabolic activity of CYP2D6 and CYP3A4.

Thymoquinone modulates nitric oxide production and improves organ dysfunction of sepsis

AIMS

The present investigation was designed to evaluate the effect of thymoquinone in a septic animal model and to explore the role of nitric oxide (NO) in the process.

MAIN METHODS

To achieve this, mice (n=12 per group) were treated in parallel with thymoquinone (0.75mg/kg/day) and/or NG-nitro-l-arginine methyl ester (L-NAME; 400μg/g/day) prior to sepsis induction with live Escherichia coli.

KEY FINDINGS

Thymoquinone significantly improved renal and hepatic functions alone and in combination with L-NAME. This was associated with less NO production and lower oxidative stress in treated animals. Tumor necrosis factor-α concentration with thymoquinone and L-NAME were 36.27±3.41pg/ml and 56.55±5.85pg/ml, respectively, as opposed to 141.11±6.46pg/ml in septic controls. Similarly, Interleukin-1α, 2, 6 and 10 levels decreased significantly upon treatment with thymoquinone and L-NAME as compared with untreated septic animals. NF-κB and NF-κB-DNA binding activity in nuclear proteins were also significantly down-regulated. Vascular responsiveness studies in isolated mouse aortae demonstrated a reduced relaxation to acetylcholine exposure in septic mice treated with thymoquinone.

SIGNIFICANCE

These findings suggest that thymoquinone prevents sequels of the multiple organ failure syndrome of sepsis by modulating the production of NO and its inflammatory sequela, and adjusting vascular responsiveness.

Effects of calcitriol on structural changes of kidney in C57BL/6J mouse model

Thisaim of the studyisto investigate the effects of calcitriol (vitamin D) on mouse kidneys under obese conditions. Male C57BL/6J mice were maintained on either low fat diet (LFD) or high fat diet (HFD) with/without calcitriol treatment (150 IU/kg/day) for 16 consecutive weeks. Results of HFD fed mice demonstrated more weight gain and showed numerous structural abnormalities in the corticomedullary region compared to those under control and LFD conditions. Near nephropathy condition in HFD mice were characterized by damage in renal tubules, including dilatation of interstitial cells and blood vessels. Furthermore, exfoliation and shedding of proximal tubular cells takes place. The conditions further worsen by thickening the basement membrane and interstitial inflammation, as evidenced by abundant interstitial debris. Additionally, a large number of degenerated mitochondria, fat droplets, lysosomal bodies' mesangial expansion, and cellular debris were found throughout the kidney. Sustained cell hypertrophy was also evident by transmission electron microscope confirming a marked increase in degeneration of cells within renal areas. No significant variances were detected in the glomerulus' area and diameter in both low and high fat diets with/without calcitriol treatment as well as inner and outer diameters of both distal and proximal tubule in all groups. Evidently, calcitriolcould act as a protective agent to normalize kidney structure in obese condition. This study suggests that calcitriol could normalize the function of kidney and protect its structural integrity in obesity.

Effects of Thymoquinone on the Pharmacokinetics and Pharmacodynamics of Glibenclamide in a Rat Model

Glibenclamide and thymoquinone plasma concentrations were analysed using a sensitive RP-HPLC method, and non-compartmental model pharmacokinetic parameters were calculated. The maximum reduction in blood glucose level was observed 3 hours following glibenclamide administration, which reached 47.4% of baseline, whereas it was reduced by 53.0% to 56.2% when co-administrated with thymoquinone. Plasma concentration of glibenclamide was increased by 13.4% and 21.8% by the co-administration of thymoquinone as single and multiple doses, respectively ( P<0.05). The AUC and T1/2 of glibenclamide were also increased respectively by 32.0% and 17.4% with a thymoquinone single dose, and by 52.5% and 92.8% after chronic treatment. Furthermore, diabetic rats treated with thymoquinone demonstrated a marked decrease in hepatic protein expressions of CYP3A2 and CYP2C11 enzymes that are responsible for the metabolism of glibenclamide. The current data suggest that thymoquinone exhibits a synergistic effect with glibenclamide on glucose level, which could be explained by reducing CYP450 activity at the protein level.

Effects of Thymoquinone on the Pharmacokinetics and Pharmacodynamics of Glibenclamide in a Rat Model

Glibenclamide and thymoquinone plasma concentrations were analysed using a sensitive RP-HPLC method, and non-compartmental model pharmacokinetic parameters were calculated. The maximum reduction in blood glucose level was observed 3 hours following glibenclamide administration, which reached 47.4% of baseline, whereas it was reduced by 53.0% to 56.2% when co-administrated with thymoquinone. Plasma concentration of glibenclamide was increased by 13.4% and 21.8% by the co-administration of thymoquinone as single and multiple doses, respectively (P<0.05). The AUC and TI/2 of glibenclamide were also increased respectively by 32.0% and 17.4% with a thymoquinone single dose, and by 52.5% and 92.8% after chronic treatment. Furthermore, diabetic rats treated with thymoquinone demonstrated a marked decrease in hepatic protein expressions of CYP3A2 and CYP2C 11 enzymes that are responsible for the metabolism of glibenclamide. The current data suggest that thymoquinone exhibits a synergistic effect with glibenclamide on glucose level, which could be explained by reducing CYP450 activity at the protein level.

Vitamin D supplementation and serum levels of magnesium and selenium in type 2 diabetes mellitus patients: gender dimorphic changes

The aim of our study was to evaluate the effects of vitamin D supplementation on circulating levels of magnesium and selenium in patients with type 2 diabetes mellitus (T2DM). A total of 126 adult Saudi patients (55 men and 71 women, mean age 53.6±10.7 years) with controlled T2DM were randomly recruited for the study. All subjects were given vitamin D3 tablets (2000 IU/day) for six months. Follow-up mean concentrations of serum 25-hydroxyvitamin D [25-(OH) vitamin D] significantly increased in both men (34.1±12.4 to 57.8±17.0 nmol/L) and women (35.7±13.5 to 60.1±18.5 nmol/L, p<0.001), while levels of parathyroid hormone (PTH) decreased significantly in both men (1.6±0.17 to 0.96±0.10 pmol/L, p=0.003) and women (1.6±0.17 to 1.0±0.14 pmol/L, p=0.02). In addition, there was a significant increase in serum levels of selenium and magnesium in men and women (p-values<0.001 and 0.04, respectively) after follow-up. In women, a significant correlation was observed between delta change (variables at six months-variable at baseline) of serum magnesium versus high-density lipoprotein (HDL)-cholesterol (r=0.36, p=0.006) and fasting glucose (r=-0.33, p=0.01). In men, there was a significant correlation between serum selenium and triglycerides (r=0.32, p=0.04). Vitamin D supplementation improves serum concentrations of magnesium and selenium in a gender-dependent manner, which in turn could affect several cardiometabolic parameters such as glucose and lipids.