Cytoprotective and enhanced anti-inflammatory activities of liposomal piroxicam formulation in lipopolysaccharide-stimulated RAW 264.7 macrophages

BACKGROUND: Liposomal drug delivery systems, a promising lipid-based nanoparticle technology, have been known to play significant roles in improving the safety and efficacy of an encapsulated drug. METHODS: Liposomes, prepared using an optimized proliposome method, were used in the present work to encapsulate piroxicam, a widely prescribed nonsteroidal anti-inflammatory drug. The cytotoxic effects as well as the in vitro efficacy in regulation of inflammatory responses by free-form piroxicam and liposome-encapsulated piroxicam were evaluated using a lipopolysaccharide-sensitive macrophage cell line, RAW 264.7. RESULTS: Cells treated with liposome-encapsulated piroxicam demonstrated higher cell viabilities than those treated with free-form piroxicam. In addition, the liposomal piroxicam formulation resulted in statistically stronger inhibition of pro-inflammatory mediators (ie, nitric oxide, tumor necrosis factor-α, interleukin-1β, and prostaglandin E2) than piroxicam at an equivalent dose. The liposome-encapsulated piroxicam also caused statistically significant production of interleukin-10, an anti-inflammatory cytokine. CONCLUSION: This study affirms the potential of a liposomal piroxicam formulation in reducing cytotoxicity and enhancing anti-inflammatory responses in vitro

Clinacanthus nutans Extracts Are Antioxidant with Antiproliferative Effect on Cultured Human Cancer Cell Lines

Clinacanthus nutans Lindau leaves (CN) have been used in traditionalmedicine but the therapeutic potential has not been explored for cancer prevention and treatment. Current study aimed to evaluate the antioxidant and antiproliferative effects of CN, extracted in chloroform, methanol, and water, on cancer cell lines. Antioxidant properties of CN were evaluated using DPPH, galvinoxyl, nitric oxide, and hydrogen peroxide based radical scavenging assays, whereas the tumoricidal effect was tested on HepG2, IMR32, NCL-H23, SNU-1, Hela, LS-174T, K562, Raji, and IMR32 cancer cells using MTT assay. Our data showed that CN in chloroform extract was a good antioxidant against DPPH and galvinoxyl radicals, but less effective in negating nitric oxide and hydrogen peroxide radicals. Chloroformextract exerted the highest antiproliferative effect on K-562 (91.28±0.03%) andRaji cell lines (88.97± 1.07%) at 10

Enhanced anti-inflammatory effects of nanoencapsulated diclofenac

This study was conducted to compare the anti-inflammatory efficacy of nanoencapsulated and free-form diclofenac in rat. Diclofenac-loaded liposomes were prepared using the proliposome method. The anti-inflammatory effects of nanoencapsulated and free diclofenac were evaluated using the carrageenan-induced paw edema, formalin-induced paw licking and cotton-pellet-induced granuloma tests in vivo. For carrageenan-induced paw edema, 2 and 20 mg/kg liposome-encapsulated diclofenac showed significant paw volume reduction compared to free form diclofenac of equivalent dosage groups. In the formalin test, significant reduction in paw-licking time was observed in late phase for both liposome-encapsulated and free-form diclofenac (2 and 20 mg/kg) with the percentage of inhibition of 28.62, 60.17% for free-form diclofenac and 31.45, 78.84% for liposome-encapsulated diclofenac, respectively. In cotton-pellet-induced granuloma test 20 mg/kg free-form diclofenac showed significant reduction in the size of granuloma in both transudative and granuloma weight with percentage of inhibition of 42.93 and 49.26%, respectively, when compared to controls. Interestingly, 20 mg/kg nanoencapsulated diclofenac showed a larger reduction of the parameter with percentage of inhibition of 48.43 and 63.55%, respectively. Collectively, these results indicated that nanoencapsulated diclofenac exhibited statistically higher efficacy than free-form diclofenac when orally administered. Hence, clinical dosage may be reduced thereby reducing the drug's adverse effects

Comparative investigation into the anti-ulcer activity of virgin coconut oil and coconut oil in pylorous ligated animal model

This current study investigated the anti-ulcer activity of 2 types of virgin coconut oil (VCO-A and VCO-B) and coconut oil (CO). Sprague-Dawley of male rats divided into 6 groups and each group consisted of ten rats. Rats were then treated with either VCO or CO and then were then anaesthetized and pyloric ligation was performed. The anaesthesia was discontinued and the animal usually recovered consciousness within less than an hour. Three hours later, the animal was then again anaesthetized and sacrificed with chloroform. Stomach removed and its content subjected to measurement of volume and pH. The results revealed VCO-B and VCO-A (100%) significantly inhibited (p < 0.001) the volume of gastric juice secreted by the control rats by 66.81% and 51.53%, respectively. Followed by CO 42.80%. While the inhibition of gastric juice for positive control rats which treated with ranitidine (100 mg/kg) was only 22.38%. The total acid output was reduced by the oils to 70.80%, 74.16% and 40.45% for VCO-A, VCO-B and CO respectively compared to control group. Ranitidine reduced the total acid output by 34.83%. In conclusion, prevention of gastric lesions in rats by VCO was found to increase the mucous and decrease the acid volume, total acid contents and ulcer scoring. The treatment of VCO affects the all parameters that influence the initiation and perpetuation of ulceration

Rapid spectrophotometric determination, characterization and anti-inflammatory efficacy evaluation of nanoencapsulated diclofenac sodium

This study was aimed to develop a simple and reproducible spectrophotometric method for the characterization of diclofenac sodium (DS) and to evaluate the efficacy of orally administered liposome encapsulated as well as free form DS in animal model. A simple, rapid and economical spectrophotometric analytical procedure with estimation in UV-visible region was performed on DS using dimethyl sulfoxide as solvent. Parameters such as time, temperature and types of solvent were studied for 20 μg/mL DS solution at 295 nm. All parameters and results of analysis were statistically validated. Liposome-encapsulated and free form DS samples were subjected to characterization study that includes entrapment efficacy determination and particle size analysis. Drug samples were further tested for their in vivo anti-inflammatory efficacy using histamine-induced paw edema test. Under optimized parameters, the Beer’s law is obeyed in range of 0.625-40 μg/mL at λmax 295 nm. A linear working range of 5-35 μg/mL with regression coefficient of 0.9978 was obtained by using seven triplicate analyses of drug samples at seven different concentrations. The limit of detection and limit of quantitation was 1.19 and 3.62 μg/mL, respectively. Result of characterization study showed that the optimum formulation, which has high entrapment efficacy of 87 %, homogenous in size (polydispersity index 0.27), stable and reproducible, were obtained by using the Pro-Lipo Duo with 10 h hydration time and 16 mg/g DS. The liposome encapsulated DS resulted in significant (P < 0.05) inhibition up to 86 % in histamine-induced paw edema test. Present study successfully demonstrated an optimized procedure as per ICH guidelines in detection and evaluation of DS. In addition, nano-encapsulation of DS using liposome was found to demonstrate a potential enhancement in therapeutic efficacy

Formulation of liposome-encapsulated piroxicam for improved therapeutic efficacies and reduced systemic toxicities

Piroxicam, a frequently prescribed nonsteroidal anti-inflammatory drug for treating various types of musculoskeletal disorders, has been associated with low oral bioavailability and delayed onset of its therapeutic activities. A prolonged usage of piroxicam also leads to broad spectrum of untoward reactions such as gastrointestinal, haematological, hepatic and renal complications. In present work, liposomal drug delivery system, a promising lipid-based nanoparticle technology, was exploited with the aim to improve therapeutic index of piroxicam. Different in vitro and in vivo experimental models were employed to reach a proof of concept for present liposomal piroxicam formulation, as well as to elucidate the underlying mechanisms of actions. A simple and reproducible proliposomes method was successfully being developed to produce liposome-encapsulated piroxicam. The most optimum liposomal formulation (ProlipoTM Duo; 12 mg piroxicam per g ProlipoTM; 10 hours hydration time; no size reduction treatment) produced highest amount of actual drug been entrapped in liposomes (800.4 mg/g ProlipoTM) and exhibited a satisfactory entrapment efficiency (15.36%). This formulation also yielded a homogenous liposomes population (polydispersity index = 0.45) with small particle size (359.95 nm). The prepared liposome-encapsulated piroxicam was stable at both room and refrigerated (2-8 ºC) temperature for at least 4 weeks. In lipopolysaccharide-stimulated RAW 264.7 macrophages model, the potential of this optimized liposomal piroxicam formulation in reducing both cytotoxicity and in vitro inflammatory responses were demonstrated. Liposome-encapsulated piroxicam exhibited a significantly (P<0.05) stronger inhibition of proinflammatory mediators (nitric oxide, tumour necrosis factor-α, interleukin-1β and prostaglandin E2) than piroxicam of equivalent dosages. Liposome-encapsulated piroxicam also resulted in significant (P<0.05) production of an anti-inflammatory cytokine (interleukin-10). Present research work also showed that the intragastrically administered liposomal piroxicam formulation was able to improve drug’s therapeutic effects in various animal models. The acetic acid-induced abdominal writhing test, formalin-induced paw-licking test as well as carrageenan-induced mechanical and thermal hyperalgesia test evidenced an increased and longer lasting peripherally-mediated antinociceptive activities by present liposomal piroxicam formulation. A lower dosage of liposomal piroxicam formulation was also shown to inhibit the Brewer’s yeast-induced hyperthermia significantly (P<0.05). In addition, carrageenan-induced paw oedema test and cotton pellet-induced granuloma test showed that liposome-encapsulated piroxicam possessed significantly (P<0.05) stronger acute and chronic anti-inflammatory effects than piroxicam, even if lower drug dosages were used to treat animals. The enhanced in vivo therapeutic activities were attributed to a better modulation in production of different inflammatory mediators such as nitric oxide, tumour necrosis factor-α, interleukin-1β and interleukin-10. Liposomal formulation also significantly (P<0.05) enhanced the inhibition of cyclooxygenase-2, but not cyclooxygenase-1 enzyme. In addition, sub-acute toxicity study revealed that rats treated with liposomal formulation exhibited less signs of toxicity. In contrast to an equivalent dosage of liposome-encapsulated piroxicam, the piroxicam caused significantly (P<0.005) lower concentration of red blood cell, haemoglobin, haematocrit, lymphocytes and platelet in complete blood count. Biochemical analysis (liver and kidney function tests) as well as histopathology assessment indicated that present liposomal formulation was able to reduce piroxicam-induced hepatotoxicity significantly (P<0.05), but not the renal dysfunction. Moreover, liposomal formulation also significantly (P<0.05) reduced macroscopic and microscopic gastric lesion in repeatedly treated rats. Further toxicity study showed that liposomal formulation resulted in a significantly (P<0.05) higher gastric mucus and pH level than equivalent dosage of piroxicam. A lower drug dosage of liposome-encapsulated piroxicam also significantly (P<0.05) increased the level of serum gastrin. In contrast to piroxicam, the liposome-ncapsulated piroxicam did not cause significant (P<0.05) reduction of prostaglandin E2 in gastric mucosa. Hence, liposomal formulation was believed to exert its gastroprotective effects through the augment of gastric mucosa defence. As a conclusion, present works successfully developed a practical liposomal piroxicam formulation with improved therapeutic efficacies and reduced systemic toxicities

Evaluation of antinociceptive activity of nanoliposome-encapsulated and free-form diclofenac in rats and mice

Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) that exhibits anti-inflammatory, antinociceptive, and antipyretic activities. Liposomes have been shown to improve the therapeutic efficacy of encapsulated drugs. The present study was conducted to compare the antinociceptive properties between liposome-encapsulated and free-form diclofenac in vivo via different nociceptive assay models. Liposome-encapsulated diclofenac was prepared using the commercialized proliposome method. Antinociceptive effects of liposome-encapsulated and free-form diclofenac were evaluated using formalin test, acetic acid-induced abdominal writhing test, Randall–Selitto paw pressure test, and plantar test. The results of the writhing test showed a significant reduction of abdominal constriction in all treatment groups in a dose-dependent manner. The 20 mg/kg liposome-encapsulated diclofenac demonstrated the highest antinociceptive effect at 78.97% compared with 55.89% in the free-form group at equivalent dosage. Both liposome-encapsulated and free-form diclofenac produced significant results in the late phase of formalin assay at a dose of 20 mg/kg, with antinociception percentages of 78.84% and 60.71%, respectively. Significant results of antinociception were also observed in both hyperalgesia assays. For Randall–Sellito assay, the highest antinociception effect of 71.38% was achieved with 20 mg/kg liposome-encapsulated diclofenac, while the lowest antinociceptive effect of 17.32% was recorded with 0 mg/kg liposome formulation, whereas in the plantar test, the highest antinociceptive effect was achieved at 56.7% with 20 mg/kg liposome-encapsulated diclofenac, and the lowest effect was shown with 0 mg/kg liposome formulation of 8.89%. The present study suggests that liposome-encapsulated diclofenac exhibits higher antinociceptive efficacy in a dose-dependent manner in comparison with free-form diclofenac

In vitro anti-diabetic activities and chemical analysis of polypeptide-k and oil isolated from seeds of Momordica charantia (bitter gourd)

The amino acid and fatty acid composition of polypeptide k and oil isolated from the seeds of Momordica charantia was analysed. The analysis revealed polypeptide k contained 9 out of 11 essential amino acids, among a total of 18 types of amino acids. Glutamic acid, aspartic acid, arginine and glycine were the most abundant (17.08%, 9.71%, 9.50% and 8.90% of total amino acids, respectively). Fatty acid analysis showed unusually high amounts of C18-0 (stearic acid, 62.31% of total fatty acid). C18-1 (oleic acid) and C18-2 (linoleic acid) were the other major fatty acid detected (12.53% and 10.40%, respectively). The oil was devoid of the short fatty acids (C4-0 to C8-0). Polypeptide k and oil were also subjected to in vitro α-glucosidase and α-amylase inhibition assays. Both polypeptide k and seed oil showed potent inhibition of α-glucosidase enzyme (79.18% and 53.55% inhibition, respectively). α-Amylase was inhibited by 35.58% and 38.02%, respectively. Collectively, the in vitro assay strongly suggests that both polypeptide k and seed oil from Momordica charantia are potent potential hypoglycemic agents