Sorafenib

Sorafenib (BAY-43-9006), marketed by Bayer as Nexavar® (USA), is anticancer drug approved by US-FDA for the treatment of unresectable hepatocellular carcinoma and advanced renal cell carcinoma. Sorafenib inhibited tumor growth and angiogenesis through targeting both the RAF/MEK/ERK pathway and receptor tyrosine kinases. This study presents a comprehensive profile of sorafenib, including detailed nomenclature, formula, elemental analysis, methods of preparation, physico-chemical characteristics, and methods of analysis (including spectroscopic, electrochemical, and chromatographic methods of analysis). Spectroscopic and spectrometric analyses include UV/vis spectroscopy, vibrational spectroscopy, nuclear magnetic resonance spectrometry ((1)H and (13)C NMR), and mass spectrometry. Chromatographic methods of analyses include thin layer chromatography and high-performance liquid chromatography. Only few stability indicating methods were found for quantification of sorafenib after exposing tablet dosage form to various stress conditions such as hydrolysis, oxidation, thermal stress, photo and UV light. However, none of these described methods were made to separate and quantify the degradation products. Pharmacology studies including pharmacodynamics, mechanism of action, pharmacokinetics and drug-drug interactions were also presented. An appropriate table and figures were attached to each of the above mentioned sections along with total of 55 references.

Formulation and characterization of novel soft nanovesicles for enhanced transdermal delivery of eprosartan mesylate

The objective of the present work was to formulate, optimize and evaluate the potential of novel soft nanovesicles i.e. nano-transfersomes, containing eprosartan mesylate (EM) for transdermal delivery. Nano-transfersomes of EM were developed using Phospholipon 90G, Span 80 (SP) and sodium deoxycholate (SDC) and characterized for vesicle size, shape, entrapment efficiency, in vitro skin permeation study and confocal laser scanning microscopy. The optimized nano-transfersomes formulation showed vesicles size of 108.53 ± 0.06 nm and entrapment efficiency of 63.00 ± 2.76%. The optimized nano-transfersomes provided an improved transdermal flux of 27.22 ± 0.29 µg/cm²/h with an enhancement ratio of 16.80 over traditional liposomes through Wistar rat skin. Confocal laser microscopy of rat skin treated with the optimized formulation showed that the formulation was eventually distributed and permeated deep into the rat skin. The present investigation has shown that the nature and concentration of surfactants (edge activators) influence immense control on the characteristics of nano-transfersomes. It was concluded that the developed nano-transfersomes surmount the limitation of low penetration ability of the traditional liposomes across the rat skin. Improved drug delivery presented by nano-transfersomes establishes this system as an encouraging dosage form for the delivery of EM via skin route.

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.

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.

Enhanced anti-inflammatory activity of carbopol loaded meloxicam nanoethosomes gel

The aim of the current investigation is to develop nanoethosomes for transdermal meloxicam delivery. The ethosomes were prepared by varying the variables such as concentrations of phospholipids 90G, ethanol, and sonication time while entrapment efficiency, vesicle size and transdermal flux were the chosen responses. Results indicate that the nanoethosomes of meloxicam provides lesser vesicles size, better entrapment efficiency and improved flux for transdermal delivery as compared to rigid liposomes. The optimized formulation (MCEF-OPT) obtained was further evaluated for an in vivo anti-inflammatory activity in rats. Optimized nanoethosomal formulation with vesicles size of 142.3nm showed 78.25% entrapment efficiency and achieved transdermal flux of 10.42μg/cm(2)/h. Nanoethosomes proved to be significantly superior in terms of, amount of drug permeated into the skin, with an enhancement ratio of 3.77 when compared to rigid liposomes. In vivo pharmacodynamic study of carbopol(®) loaded nanoethosomal gel showed significant higher percent inhibition of rat paw edema compared with oral administration of meloxicam. Our results suggest that nanoethosomes are an efficient carrier for transdermal delivery of meloxicam.

Erlotinib

Erlotinib (OSI-774), marketed by Genentech as Tarceva®, is anticancer drug approved by US-FDA for the treatment of Non-Small Cell Lung Cancer (NSCLC) and Pancreatic Cancer. Erlotinib inhibited epidermal growth factor receptor (EGFR) that blocks tumor cell division, produces cell cycle arrest, and initiates programmed cell death in EGFR-overexpressing human tumor cells. This study presents a comprehensive profile of erlotinib, including detailed nomenclature, formula, elemental analysis, methods of preparation, physico-chemical characteristics, and methods of analysis (including spectroscopic, electrochemical, and chromatographic methods of analysis). Spectroscopic and spectrometric analyses include UV/vis spectroscopy, vibrational spectroscopy, nuclear magnetic resonance spectrometry ((1)H and (13)C NMR), and mass spectrometry. Chromatographic methods of analyses include thin layer chromatography, and high-performance liquid chromatography. Pharmacology of erlotinib including pharmacodynamics, mechanism of action, pharmacokinetics and drug-drug interactions were also presented. An appropriate table and figures were attached to each of the above mentioned sections along with total of 48 references.

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.

Eprosartan mesylate loaded bilosomes as potential nano-carriers against diabetic nephropathy in streptozotocin-induced diabetic rats

The objective of the present study was to formulate eprosartan mesylate loaded nano-bilosomes and investigates its potential for controlling streptozotocin induced diabetes nephropathy in Wistar rats. The eprosartan mesylate loaded nano-bilosomes comprising of various ratios of soybean phosphatidylcholine/sodium deoxycholate were prepared by thin film hydration technique. The prepared formulations were evaluated for vesicles size, polydispersity index, zeta potential and entrapment efficiency. Further the optimized formulation was characterized for vesicles morphology, and its efficacy for the management of diabetic nephropathy in Wistar rats. The optimized eprosartan mesylate loaded nano-bilosomes exhibited vesicles size, polydispersity index, zeta potential and entrapment efficiency of 63.88±3.46nm, 0.172±0.026, -30.40±2.75mV and 61.19±0.88% respectively. In vivo activity demonstrated that the prepared eprosartan mesylate loaded nano-bilosomes formulation demonstrated a nephro-protecting outcome as shown by the substantial decrease in serum creatinine, urea, lactate dehydrogenase, total albumin, and malondialdehyde. Additionally, an oral administration of eprosartan mesylate loaded nano-bilosomes decreases the raised expressions of Angiotensin II type 1 receptor, inducible nitric oxide synthase, and transforming growth factor-β1 in Wistar rats. Further, histopathological examination established the nephro-protective effect of prepared formulation. In conclusion, the research work in the paper suggests that the prepared eprosartan mesylate loaded nano-bilosomes could serve as a practical oral formulation for diabetic nephropathy in future therapy and may offer potential benefits in cases with hypertension and renal disease.

Sinapic Acid Ameliorates Acetic Acid-Induced Ulcerative Colitis in Rats by Suppressing Inflammation, Oxidative Stress, and Apoptosis

Background: Ulcerative colitis (UC) is a long-term condition which results in inflammation and ulcers of the colon and rectum. The key indications of active disease are abdominal pain and diarrhea mixed with blood. Aims: We explore the underlying colon protective mechanism of sinapic acid (SA) against acetic acid (AA) induced ulcerative colitis in rats. The implications of inflammation, oxidative stress, and apoptosis are studied. Methodology: Twenty-four rats were distributed into four categories, normal control (NC), ulcerative colitis (UC), ulcerative Colitis with SA 40 mg/kg (SA 40 mg/kg + AA), and ulcerative colitis with prednisolone (PRDL 10 mg/kg + AA), and were pretreated orally with saline, saline and SA (40 mg/kg/day) or PRDL (10 mg/kg/day) respectively, for 7 days. UC was prompted by trans-rectal administration of 4% AA on the 5th day, colon tissues were surgically removed for gross morphology and histological inspection, oxidative stress, and inflammatory markers and immunoblot analysis of Bax, caspase-3, and Bcl-2. Results: Macroscopic and histological inspection demonstrated that both SA 40 mg/kg and PRDL (10 mg/kg/day) significantly ameliorates colonic injuries. In addition, both pretreatments significantly ameliorates AA-induced UC, oxidative stress, as indicated by suppressed malondialdehyde (MDA), nitric oxide (NO) levels and restoring antioxidant/oxidant balance as indicated by catalase and glutathione levels, suppressed inflammation via inhibiting cytokines TNF-α, IL-6, inflammatory markers MPO, PGE2, COX-2 and NF-κB and inhibiting the protein expression of Bax and caspase-3 apoptotic protein and increasing the anti-apoptotic protein, Bcl-2 thereby inhibiting apoptosis. Conclusion: Sinapic acid significantly ameliorates AA induced UC in rats by suppressing inflammation, oxidative stress, and apoptosis in colonic tissues which exhibits its potential for the management of UC.

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.

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.

Sorbitane Monostearate and Cholesterol based Niosomes for Oral Delivery of Telmisartan

BACKGROUND

Niosomes are non-ionic surfactant vesicles used as drug carriers for encapsulating both hydrophobic and hydrophilic drugs. The aim of the present study was to prepare and characterize niosomes formulations for oral delivery of telmisartan and evaluated for its antihypertensive activity.

METHOD

Telmisartan loaded niosomes were prepared using thin film hydration method by varying the Span 60 and cholesterol at several molar ratios and characterized for vesicles size, polydispersity index, zeta potential, entrapment efficiency. The in vivo antihypertensive study of optimized formulation and molecular impact of angiotensin II type-1 receptor (AT1R) messenger Ribonucleic acid (mRNA) and protein expression on smooth vascular muscles of aorta was determined by real-time polymerase chain reaction (RT-PCR) and western blot analysis in Wistar albino rats.

RESULTS

The optimized niosomes formulation NS6 presented vesicles size of 618.47 nm, polydispersity index of 0.86, with entrapment efficiency of 83.83% and possesses negative charge. In vivo study showed that the optimized formulation could reduce the systolic blood pressure in methyl prednisolone acetate induced hypertensive rats in close proximity to normal range of systolic blood pressure and maintain it over an extended period. In addition, telmisartan loaded niosomes treatment to hypertensive rats significantly attenuates the raised mRNA level and protein level of AT1R gene in comparison to hypertensive rats.

CONCLUSION

Results of present study confer the potential of developed niosomes as suitable carriers for improved oral delivery of telmisartan.

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.

Delivery of Insulin via Skin Route for the Management of Diabetes Mellitus: Approaches for Breaching the Obstacles

Insulin is used for the treatment of diabetes mellitus, which is characterized by hyperglycemia. Subcutaneous injections are the standard mode of delivery for insulin therapy; however, this procedure is very often invasive, which hinders patient compliance, particularly for individuals requiring insulin doses four times a day. Furthermore, cases have been reported of sudden hypoglycemia occurrences following multidose insulin injections. Such an invasive and intensive approach motivates the quest for alternative, more user-friendly insulin administration approaches. For example, transdermal delivery has numerous advantages, such as prolonged drug release, low variability in the drug plasma level, and improved patient compliance. In this paper, the authors summarize different approaches used in transdermal insulin delivery, including microneedles, chemical permeation enhancers, sonophoresis, patches, electroporation, iontophoresis, vesicular formulations, microemulsions, nanoparticles, and microdermabrasion. Transdermal systems for insulin delivery are still being widely researched. The conclusions presented in this paper are extracted from the literature, notably, that the transdermal route could effectively and reliably deliver insulin into the circulatory system. Consistent progress in this area will ensure that some of the aforementioned transdermal insulin delivery systems will be introduced in clinical practice and commercially available in the near future.

CYP2C19 genetic polymorphism in Saudi Arabians

The main objective of this study was to evaluate CYP2C19 genetic polymorphism in a Saudi Arabian population by determining the frequencies of CYP2C19*2, *3, *4, *6, *7 and *17 alleles and their relevant genotypes. Genomic DNA was isolated from 192 healthy Saudi Arabians, representing different geographical regions, and genotyping of the selected CYP2C19 variants was carried out by direct sequencing after PCR amplification. The allelic frequency of heterozygous CYP2C19*2 was 8.2% with only one individual found to carry the homozygous genotype of this defective allele. None of the other investigated poor metabolizer alleles (i.e. CYP2C19*3, *4, *6 and *7) was detected in the study population. About 46% of the examined volunteers were found to carry CYP2C19*17 genotype (37.5% heterozygous and 8.1% homozygous of the defective allele) with an overall CYP2C19*17 allelic frequency of 26.9%. In addition, a novel CYP2C19 SNP (G356A) and another very rare SNP (C336T) have been identified in this study with a frequency of about 50% for each. Further studies are required to evaluate the metabolic and clinical relevance of CYP2C19*17, G356A and C336T in the Saudi Arabian population.

Hepatoprotective effect of Commiphora myrrha against d-GalN/LPS-induced hepatic injury in a rat model through attenuation of pro inflammatory cytokines and related genes

CONTEXT

Commiphora myrrha (Burseraceae), a shrub resembling a small tree, has been used for several centuries for the treatment of various diseases.

OBJECTIVE

This study investigates the hepatoprotective activity of C. myrrha ethanol extract against d-galactosamine/lipopolysaccharide (d-GalN/LPS)-induced acute hepatic injury in an animal model.

MATERIALS AND METHODS

Rats were pretreated with ethanolic extract C. myrrha (250 and 500 mg/kg; p.o.) for 7 d prior to the induction of an acute phase response by d-GalN/LPS. Animals were sacrificed 24 h after d-GalN/LPS (800 mg/kg and 50 µg/kg i.p.) administration for the biochemical and histological analyses.

RESULTS

The administration of d-GalN/LPS increased plasma aminotransferases (174.47 ± 4.5761 and 260.96 ± 1.9839 µkat/l) and total bilirubin levels (1.012 ± 0.0288 mg/dl), which were attenuated by C. myrrha treatment. Hepatic lipid peroxidation activity and nitric oxide content also increased, while the antioxidant activity measured by GSH (0.76 nmol/g protein), SOD (81.91 U/mg protein), and CAT (15.78 U/mg protein) was reduced. Commiphora myrrha provided significant restoration of GSH (0.815 nmol/gm protein), SOD (140.57 U/mg protein), and CAT (27.02 U/mg protein) levels. Furthermore, the acute phase response elicited by d-GalN/LPS administration enhanced mRNA expressions of TNF-α, IL-6, IL-10, iNOS-2, and HO-1, which were ameliorated by C. myrrha treatment.

DISCUSSION AND CONCLUSION

These findings indicate that C. myrrha considerably reduces the oxidative stress of d-GalN/LPS-induced hepatic injury via multiple pathways including adown regulation of inflammatory mediators and cytokines. Such a property might be sufficient to combat cellular damage caused by various conditions that resemble fulminant hepatitis and could be of a potential clinical application.

Understanding and managing oral bioavailability: physiological concepts and patents

Oral delivery of poorly bioavailable therapeuticals is challenging. The challenges are more serious when physiological factors of gut such as cytochrome P450, P-glycoprotein, permeability, pH triggered precipitation and degradation are responsible for poor bioavailability. P-Glycoprotein mediated multidrug resistance is on high agenda for anti-cancer drugs. The present article compiled different methodologies used to curb these challenges of bioavailability. The concepts of poor bioavailability are illustrated along with possible management. Numerous relevant patents for bioavailability enhancement are also highlighted. Though, there is no universal approach for bioavailability enhancement, the drug related challenges are managed by altering its physicochemical characteristics or employing formulation technology, while the effects of physiological factors are minimized by using efflux transport inhibitor or cytochrome P-450 inhibitor or prodrug or through formulation technologies (enteric coating or microenvironment of pH etc.).

Effect of black seed on dextromethorphan O- and N-demethylation in human liver microsomes and healthy human subjects

OBJECTIVE

To investigate the effects of black seed on the metabolic activities of CYP3A4 and CYP2D6 in human liver microsomes and in human subjects using dextromethorphan as a probe drug.

METHODS

CYP2D6-mediated O-demethylation and CYP3A4-mediated N-demethylation of dextromethorphan (DEX) to dextrorphan (DOR) and 3-methoxymorphinan (3-MM), respectively, were utilized to assess the metabolic activities of the two enzymatic pathways. In the in vitro experiments, DEX was incubated with microsomes and NADPH in absence or presence of black seed extract (10-100 microg/ml) and the formation of the metabolites were measured by HPLC. In the clinical study, four healthy volunteers received a single oral dose of DEX 30 mg alone in phase I, and along with last dose of black seed (2.5 g twice daily for seven days) in phase II. Activities of the two enzymes were evaluated based on the urinary metabolic ratios (MRs), which were calculated from eight-hour urine collections. DEX and its metabolites were assayed in urine samples by HPLC following a liquid-liquid extraction.

RESULTS

Black seed extracts significantly inhibited the formation of both metabolites in microsomes. The maximum inhibition was observed at the highest extract concentration (i.e., 100 microg/ml), which was about 80% and 60% for DOR and 3-MM, respectively. In the clinical study, the urinary MRs of DEX/DOR and DEX/3-MM increased by factors of 127 and 1.6-fold, respectively, after consumption of black seed.

CONCLUSION

Black seed significantly inhibited CYP2D6 and CYP3A4 mediated metabolism of DEX in human liver microsomes and healthy human volunteers indicating that it has the potential to interact with CYP2D6 and CYP3A4 substrates.

High prevalence of CYP2D6*41 (G2988A) allele in Saudi Arabians

The main objective of this study was to evaluate CYP2D6 genetic polymorphism in a Saudi Arabian population by determining the frequencies of CYP2D6*41, CYP2D6*29, CYP2D6*3, CYP2D6*6 and CYP2D6*14 alleles. Genomic DNA was isolated from 192 healthy Saudis representing different geographical regions, and genotyping of the selected CYP2D6 variants was carried out by direct sequencing. The allelic frequency of CYP2D6*41 was found to be 18.4%, and that of CYP2D6*29 to be 2.9%. The other investigated alleles were either not detected or rarely present in the study population. In addition, two commonly shared single nucleotide polymorphisms (SNPs) and two very rare SNPs among CYP2D6 alleles were detected. Further studies are therefore, required to evaluate the metabolic and clinical relevance of CYP2D6*41 in Saudi Arabians.

Development and biological evaluation of vesicles containing bile salt of telmisartan for the treatment of diabetic nephropathy

The aim of present study was to develop and evaluate vesicles containing bile salt formulation of telmisartan for the treatment of diabetic nephropathy. Different vesicles containing bile salt formulations were developed by varying ratios of soybean phosphatidylcholine and sodium deoxycholate. Prepared formulations were characterized for their size, polydispersity index, zeta potential, morphology and entrapment efficiency. Further, the renoprotective outcome of optimized formulation was studied in streptozotocin-induced diabetic nephropathy rat model. Results of the present study demonstrated that the average vesicles size, polydispersity index, zeta potential and entrapment efficiency were found to be in the range of 64.98 ± 1.40 to 167.60 ± 6.46 nm, 0.02 ± 0.04 to 0.31 ± 0.01, -24.30 ± 1.39 to -42.60 ± 6.67 mV and 29.68 ± 1.08% to 77.21 ± 0.52%, respectively. Further, the best chosen formulation F4 presented vesicles size, polydispersity index, zeta potential and entrapment efficiency of 64.98 ± 1.40 nm, 0.24 ± 0.02, -35.40 ± 1.48 mV and 77.21 ± 0.52%, respectively. In addition, formulation F4 improved the biological indices in streptozotocin-induced diabetic nephropathy in rats. It was concluded that prepared formulation exerts a valuable results on diabetic nephropathy and it may be a potential pharmaceutical dosage form for the treatment of diabetic nephropathy.