Kusnandar Anggadiredja

Endocannabinoid System Modulates Relapse to Methamphetamine Seeking: Possible Mediation by the Arachidonic Acid Cascade

We clarified the modulating action of the endocannabinoid system, and its possible mediation by the arachidonic acid cascade, on the reinstatement of methamphetamine (METH)-seeking behavior, using the intravenous self-administration paradigm in rats. Following 12 days of self-administration of METH, the replacement of METH with saline resulted in a gradual decrease in lever press responses (extinction). Under extinction conditions, METH-priming or re-exposure to cues previously paired with METH infusion markedly increased the responses (reinstatement of drug-seeking). The cannabinoid CB1 receptor antagonist, SR141716A, blocked this behavior. Although the cannabinoid agonist, Δ8-tetrahydrocannabinol (THC), had no effects by itself, coadministration of the agonist and METH at small doses reinstated the drug-seeking behavior. THC attenuated the effects of the reinstatement-inducing dose of METH, but enhanced the effect of cues. Either given repeatedly during the extinction or singly, 24 h before the first METH-priming or cues challenge, THC suppressed the reinstatement. In another set of experiments, we found that diclofenac, a cyclooxygenase inhibitor, also attenuated the reinstatement induced by exposure to cues or drug-priming. These results suggest that the endocannabinoid system, through possible mediation by the arachidonic acid cascade, serves as a modulator of the reinstating effects of METH-priming and cues. Extending the current view on the treatment of drug dependence, these results indicate that endocannabinoid-activating substances as well as cyclooxygenase inhibitors may be promising as antirelapse agents.

Naltrexone attenuates cue- but not drug-induced methamphetamine seeking: a possible mechanism for the dissociation of primary and secondary reward

The present study was aimed to clarify the role of the opioid system in the reinstatement of methamphetamine (METH)-seeking behavior in METH self-administering rats. Following 12 days of self-administration of METH, the replacement of METH with saline resulted in a gradual decrease in lever press responses (extinction). Under extinction conditions, METH-priming or re-exposure to cues previously paired with METH infusion markedly increased the responses (reinstatement of drug-seeking). Naltrexone administered 30 min before re-exposure to METH-associated cues attenuated reinstatement of drug-seeking behavior. On the other hand, administration of this antagonist had no effect on the reinstatement induced by METH-priming. We discussed these findings in relation with the dissociation of primary and secondary reward, suggesting that an opioid mechanism is responsible for this dissociation. Further, these results indicate the possibility of using naltrexone as an anti-relapse agent.

Nicotine attenuates relapse to methamphetamine-seeking behavior (craving) in rats

Abstract: This study clarifies the modulating action of the nicotinic cholinergic system on reinstatement of methamphetamine (MAP)‐seeking behavior (craving) using an intravenous, self‐administration paradigm in rats. After self‐administration of MAP for 10 days, replacing MAP with saline solution (MAP withdrawal) gradually decreased lever‐pressing responses. On the sixth day of MAP withdrawal, MAP (1.0 mg/kg, i.p.)‐priming injection significantly increased lever‐pressing responses (reinstatement of MAP‐seeking behavior). This MAP‐seeking behavior was attenuated by repeated nicotine administration for 5 days during MAP withdrawal, and this attenuating effect was antagonized by the nicotinic antagonist mecamylamine. These results suggest that the appearance of MAP‐seeking behavior may be due to inactivation of the nicotinic cholinergic neuron. Furthermore, it is suggested that nicotinic activating agents may be useful in preventing relapse to drug abuse.

Prostaglandin E2 attenuates SR141716A-precipitated withdrawal in tetrahydrocannabinol-dependent mice.

The present study aimed to clarify the role of the arachidonic acid cascade in mediating the expression of withdrawal signs in cannabinoid-dependent mice. Mice were injected with Delta(8)-tetrahydrocannabinol (THC) at 20 mg/kg (i.p.) every 12 h, 11 times. When SR141716A, a specific cannabinoid CB1 receptor antagonist, at 10 mg/kg (i.p.) was given 4 h after the last THC injection, withdrawal signs such as forepaw licking, facial preening, grooming, forepaw tremor, head shakes and weight loss were clearly observed. PGE(2) at 0.1, 1.0 and 3.2 microg (per animal; i.c.v.) given prior to SR141716A (10 mg/kg, i.p.) dose-dependently decreased the number of forepaw licking, facial preening, grooming and forepaw tremor episodes. Instead of SR141716A, a cyclooxygenase inhibitor diclofenac at 10 mg/kg (i.p.) also precipitated these withdrawal signs. The results suggest that the expression of THC withdrawal is due to a decrease in prostaglandin levels through inactivation of the arachidonic acid cascade in the brain.

Intraoral Film Containing Insulin-Phospholipid Microemulsion: Formulation and In Vivo Hypoglycemic Activity Study

Non-invasive administration of insulin is expected for better diabetes mellitus therapy. In this report, we developed intraoral preparation for insulin. Insulin was encapsulated into nanocarrier using self-assembly emulsification process. To increase lipophilicity of insulin, it was dispersed in phospholipid resulted in insulin-phospholipid solid dispersion. The microemulsion formula was established from our previous work which contained glyceryl monooleate (GMO), Tween 20, and polyethylene glycol (PEG 400) in a ratio of 1:8:1. To confirm the formation of insulin-phospholipid solid dispersion, PXRD, FTIR spectroscopy, and Raman spectroscopy were performed. Then, the microemulsion was evaluated for droplet size and distribution, zeta potential, entrapment efficiency, physical stability, and Raman spectroscopy. In addition, microemulsion with expected characteristic was evaluated for in vitro release, in vitro permeation, and in vivo activity. The droplets size of ∼100 nm with narrow distribution and positive charge of +0.56 mV were formed. The insulin encapsulated in the oil droplet was accounted of >90%. Water-soluble chitosan seems to be a promising film matrix polymer which also functioned as insulin release controller. Oral administration of insulin microemulsion to healthy Swiss-Webster mice showed hypoglycemic effect indicating the success of this protein against a harsh environment of the gastrointestinal tract. This effectiveness significantly increased by fourfold as compared to free insulin. Taken together, microemulsion seems to be a promising carrier for oral delivery of insulin.

Decrease in prostaglandin level is a prerequisite for the expression of cannabinoid withdrawal: a quasi abstinence approach.

Cannabinoid withdrawal has been indicated in both human and animal subjects. One of pathways proposed to facilitate cannabinoid action is the arachidonic acid cascade. Previously, we have shown that prostaglandin attenuated the expression of withdrawal signs in tetrahydrocannabinol-dependent mice. It follows that the cascade might participate in the expression of cannabinoid withdrawal. We utilized a quasi abstinence approach (the induction of a state of cannabinoid withdrawal without giving any cannabinoid substances in a naïve animal) to describe the relationship between the change in prostaglandin level, an end product of the arachidonic acid cascade, and the expression of cannabinoid withdrawal. Administration of 10 mg/kg diclofenac, a prostaglandin synthesis inhibitor, i.p. 30 min before SR 141716A induced cannabinoid withdrawal signs in naïve mice, which were comparable to the true abstinence in cannabinoid-tolerant mice. In turn, 10 mg/kg Delta(8)-THC i.p., given 15 min prior to SR 141716A, blocked the expression of these signs. These results suggested that the decrease in prostaglandin level is a prerequisite for the expression of cannabinoid withdrawal.

The In Vitro–In Vivo Safety Confirmation of PEG-40 Hydrogenated Castor Oil as a Surfactant for Oral Nanoemulsion Formulation

Evaluation on the safety use of high concentration of polyoxyl 40 (PEG-40) hydrogenated castor oil as a surfactant for oral nanoemulsion was performed in Webster mice. As previously reported, nearly 20% of PEG-40 hydrogenated castor oil was used to emulsify the glyceryl monooleate (GMO) as an oil to the aqueous phase. Thermodynamically stable and spontaneous nanoemulsion was formed by the presence of co-surfactant polyethylene glycol 400 (PEG-400). Standard parameters were analyzed for nanoemulsion including particle size and particle size distribution, the surface charge of nanoemulsion, and morphology. To ensure the safety of this nanoemulsion, several cell lines were used for cytotoxicity study. In addition, 5000 mg/kg body weight (BW) of the blank nanoemulsion was given orally to Webster mice once a day for 14 days. Several parameters such as gross anatomy, body weight, and main organs histopathology were observed. In particular, by considering the in vivo data, it is suggested that nanoemulsion composed with a high amount of PEG-40 hydrogenated castor oil is acceptable for oral delivery of active compounds.

Evaluation of Rational Drug Use for Acute Pharyngitis Associated with the Incidence and Prevalence of the Disease at Two Community Health Centers in Indonesia

According to Indonesia’s Result of Basic Health Research of 2013, prevalence of acute respiratory infection in 2007 and 2013 were not significantly different (25.5% and 25.0%, respectively). Identifying the cause of acute pharyngitis is a key point in determining the optimal treatment. The main purpose is to evaluate the rational use of drugs and its irrational impact as well as the correlation of the drug use with the incidence and prevalence of acute pharyngitis. This study was a descriptive and observational study, carried out retrospectively and concurrently at two community health centers located in Bandung and Cimahi, Indonesia. There was overprescription of antibiotics in 80.01% of prescription cases, with a total of 8.98% being non-treatment option, and 62.43% being irrational use of corticosteroids. The incidence and prevalence of acute pharyngitis at one health center in Bandung were 2.45% and 2.31%, respectively, with an irrationality rate of 83.82%. Those recorded at one health center in Cimahi were 2.11% incidence and 2.00% prevalence with an irrational rate of 91.29%. It can be concluded that there is still an irrational use of medicines in the treatment of acute pharyngitis in community health centers. The higher incidence and prevalence might indicate the declining quality of health services.

Evaluation of adverse effects of mutein forms of recombinant human interferon alpha-2b in female swiss webster mice.

Purpose. We successfully developed recombinant human interferon alpha-2b (rhIFN-α2b) and mutein forms through the site-directed mutagenesis technique. The mutein forms were developed by substituting cysteins at positions 2 and 99 with aspartic acids. The potential adverse effects of these rhIFN-α2bs were assessed by acute and subchronic studies. Methods. In the acute study, rhIFN-α2bs were subcutaneously administered to mice at a single dose of 97.5 μg/kg, 975 μg/kg, and 9.75 mg/kg BW and were observed for 14 days. In the subchronic study, single dose of 1.95 μg/kg and 19.5 μg/kg, respectively, was given subcutaneously every 3 days for 45 days. Results. No death as well as abnormality in body weight, behavior, presentation of main organs, and value of plasma SGPT and SGOT was observed. Wild type and mutein rhIFN-α2bs did not show significant adverse effects at dose up to 9.75 mg/kg BW. Administration of these rhIFN-α2bs given repeatedly did not induce any adverse effect. Conclusion. These results suggest that our rhIFN-α2bs are safe. However, further study is still needed to clarify the safety issue before use in clinical trial.