Yokukansan suppresses neuroinflammation in the hippocampus of mice and decreases the duration of lipopolysaccharide- and diazepam-mediated loss of righting reflex induced by pentobarbital.

Neuroinflammation is associated with the development of hypoactive delirium, which results in poor clinical outcomes. Drugs effective against hypoactive sur have not yet been established. Yokukansan has an anti-neuroinflammatory effect, making it potentially effective against hypoactive delirium. This study aimed to examine the effect of Yokukansan on the pentobarbital-induced loss of righting reflex duration extended with lipopolysaccharide (LPS)-induced neuroinflammation and diazepam-induced gamma-aminobutyric acid receptor stimulation in a mouse model. The active ingredients in Yokukansan and its anti-neuroinflammatory effect on the hippocampus were also investigated. Furthermore, we examined the in vitro anti-inflammatory effects of Yokukansan on LPS-stimulated BV2 cells, a murine microglial cell line. Findings revealed that treatment with Yokukansan significantly decreased the duration of pentobarbital-induced loss of righting reflex by attenuating the LPS-induced increase in interleukin-6 and tumor necrosis factor-alpha levels in the hippocampus. Moreover, treatment with Yokukansan significantly decreased the number of ionized calcium-binding adapter molecule-1-positive cells in the hippocampal dentate gyrus after 24 h of LPS administration. In addition, glycyrrhizic acid, an active ingredient in Yokukansan, partially decreased the duration of pentobarbital-induced loss of righting reflex. Treatment with Yokukansan also suppressed the expression of inducible nitric oxide, interleukin-6, and tumor necrosis factor mRNA in LPS-stimulated BV2 cells. Thus, these findings suggest that Yokukansan and glycyrrhizic acid may be effective therapeutic agents for treating neuroinflammation-induced hypoactive delirium.

Babao Dan Alleviates 5-Fluorouracil-Induced Intestinal Damage via Wnt/ß-Catenin Pathway.

OBJECTIVE: To evaluate the protective function of Babao Dan (BBD) on 5-flurouracil (5-FU)-induced intestinal mucositis (IM) and uncover the underlying mechanism. METHODS: A total of 18 male mice were randomly divided into 3 groups by a random number table, including control, 5-FU and 5-FU combined BBD groups, 6 mice in each group. A single intraperitoneal injection of 5-FU (150 mg/kg) was performed in 5-FU and 5-FU combined BBD groups on day 0. Mice in 5-FU combined BBD group were gavaged with BBD (250 mg/kg) daily from day 1 to 6. Mice in the control group were gavaged with saline solution for 6 days. The body weight and diarrhea index of mice were recorded daily. On the 7th day, the blood from the heart of mice was collected to analyze the proportional changes of immunological cells, and the mice were subsequently euthanized by mild anesthesia with 2% pentobarbital sodium. Colorectal lengths and villus heights were measured. Intestinal-cellular apoptosis and proliferation were evaluated by Tunel assay and immunohistochemical staining of proliferating cell nuclear antigen, respectively. Immunohistochemistry and Western blot were performed to investigate the expressions of components in Wnt/ß-catenin pathway (Wnt3, LRP5, ß-catenin, c-Myc, LRG5 and CD44). RESULTS: BBD obviously alleviated 5-FU-induced body weight loss and diarrhea, and reversed the decrease in the number of white blood cells, including monocyte, granulocyte and lymphocyte, and platelet (P<0.01). The shortening of colon caused by 5-FU was also reversed by BBD (P<0.01). Moreover, BBD inhibited apoptosis and promoted proliferation in jejunum tissues so as to reduce the intestinal mucosal damage and improve the integrity of villus and crypts. Mechanically, the expression levels of Wnt/ß -catenin mediators such as Wnt3, LRP5, ß-catenin were upregulated by BBD, activating the transcription of c-Myc, LRG5 and CD44 (P<0.01). CONCLUSIONS: BBD attenuates the adverse effects induced by 5-FU via Wnt/ß-catenin pathway, suggesting it may act as a potential agent against chemotherapy-induced intestinal mucositis.

Homomeric beta 1 gamma-aminobutyric acid A receptor-ion channels: evaluation of pharmacological and physiological properties.

The ubiquitous distribution of gamma-aminobutyric acid A (GABAA) receptor beta subunits throughout the central nervous system is in accord with a vital role in receptor structure and function. Homomeric beta subunits have been reported to be either GABA-gated or capable of forming anion-selective channels that lacked GABA-gating properties. With electrophysiological recording techniques, we examined the properties of the murine Beta 1 subunit, addressed whether the homomeric receptor is expressed independently from the host cell's genome, and investigated whether these channels can open spontaneously. Murine beta 1 subunits, expressed in Xenopus oocytes or A293 cells, were unaffected by GABA or bicuculline; however, the resting membrane conductances were reduced by picrotoxin, zinc, or penicillin-G. In comparison, the expression of bovine beta1 subunits formed GABA-gated C1- channels. For murine beta 1 subunits, both pentobarbitone and propofol increased the membrane conductance, although the benzodiazepine ligands flurazepam, flumazenil, and methyl-6,7-dimethoxy-4 ethyl-beta-carboline-3-carboxylate were inactive. Oocytes injected with murine beta 1 cRNA in the presence of actinomycin D (to block host cell DNA transcription) expressed beta1 channels that were indistinguishable from those derived from previous cDNA injections in cells capable of normal transcription. Single-channel recording from murin beta 1 cDNA-injected oocytes revealed spontaneously opening channels with a main state conductance of 18 pS. Picrotoxin inhibited the channel openings by reducing the probability of opening. We concluded that murine beta 1 subunits can form functional ion channels that are not gated by GABA but can be closed by some noncompetitive GABA antagonists. Interestingly, previous observations of spontaneously opening ion channels with properties similar to those found for the murine beta 1 receptor suggest that a limited expression of homomeric beta subunit-ion channels may exist in vivo.

[Changes in pentobarbital hypnosis and hepatic metabolism in streptozotocin-diabetic mice].

The present study deals with the hypnotic effect of pentobarbital (Pento) in relation to its metabolism in hepatic microsomes in streptozotocin (STZ, 170 mg/kg, i.p.) injected mice. Liver weight (mg/10 g body wt.) of STZ-treated mice was larger than that of the controls throughout the experimental period. Although the shortening of sleeping time induced by Pento (60 mg/kg, i.p.) was always observed, Pento-metabolizing enzyme activity (by the method of Kato et al., 1964) increased in mice with diabetes for 2 and 4 weeks but decreased in mice with diabetes for 8 weeks. Induction following phenobarbital (100 mg/kg, s.c.) and inhibition by SKF 525-A (10 mg/kg, i.p.) of hepatic metabolizing enzyme were found in both control and mice with diabetes for 2, 4 and 8 weeks, but these were not definitely correlated to their hepatic Pento-metabolizing enzyme activities. STZ-induced hyperglycemia and shortening of sleeping time by Pento were completely prevented by the pretreatment with nicotinamide (500 mg/kg, i.p.). NPH-insulin injection partially decreased hyperglycemia in STZ-diabetic mice, but sleeping time by Pento was not significantly affected. These results suggest that the hyposensitivity to Pento in STZ-diabetic mice is partially related to an abnormality of metabolism in liver such as the hyperglycemic state.

Effect of dietary fats and proteins on drug metabolism.

Rats were given diets ad libitum which varied in the amount (5 or 15%) and kind of fat [coconut oil (CNO) vs corn oil (CO)]. Animals were injected either with hexobarbital or pentobarbital and sleeping time was recorded. With animals eating a low fat diet, there were slight differences between the CNO vs CO groups. At the higher fat level, animals receiving the polyunsaturated diet slept more than twice as long as compared to animals eating a diet with saturated oil. Simultaneous injection with carbon tetrachloride significantly increased the sleeping time between the two dietary fat groups. Also, the kind of protein and level of fat in the diet had an influence on sleeping times. It was concluded that both the quality and quantity of fat as well as the quality of the protein can influence drug metabolism.

Effect of endosulfan pretreatment on organ weights and on pentobarbital hypnosis in rats.

The effects of endosulfan on the weights of the liver, adrenal and ovary, on pentobarbital blood and brain levels and on sleeping time (ST) have been investigated in female rats after daily oral doses of 0, 1.0, 2.5 and 5.0 mg/kg for a period of 7 or 15 days. No significant change in body weight was observed. With higher doses (2.5--5.0 mg/kg) the liver weight was significantly increased, but ovary and adrenal weights did not increase. Endosulfan treatment shortened sleeping time, while induction time was significantly increased. The concentration of pentobarbital in the blood and brain of rats after 30 min and upon awakening indicated that there was a significant decrease at 30 min. No change at awakening was observed in endosulfan-treated rats as compared to controls. It is suggested tha endosulfan may shorten the duration of pentobarbital-induced sleep, perhaps by induction of hepatic microsomal enzyme activity.

Neurotensin: central nervous system effects of a hypothalamic peptide.

The central administration of neurotensin, an endogenous hypothalamic tridecapeptide, produces a marked dose-related decrease in body temperature of mice and rats at an ambient temperature of 25 degrees C. This effect is even more pronounced when mice are placed at 4 degrees C to increase the rate of decline of body temperature. Other sequelae observed after central administration of neurotensin are decreases in locomotor activity in rats and a marked dose-related enhancement in pentobarbital-induced mortality, sedation and hypothermia. This latter effect was shown to be due to a significant reduction in the metabolic degradation of the barbiturate. None of the above-mentioned effects are observed after peripheral neurotensin administration, suggesting that this peptide does not readily cross the blood-brain barrier. Neurotensin appears to be one of a growing list of neuropeptides that can affect CNS function.

Effects of 1,1,1-trichloroethane administered by different routes and in different solvents on barbiturate hypnosis and metabolism in mice.

A 24-hr inhalation of 1,1,1-tricholoroethane (methylchloroform), 3,000 ppm, reduced pentobarbital hypnosis and increased hexobarbitaloxidation by the 9,000 x g liver supernatant fraction in male mice. On the other hand, an ip injection of methylchloroform, l ml/kg, increased the duration of pentobarbital hypnosis and reduced hexobarbital metabolism by the liver microsomal enzymes. The potentioating effect of methylchloroform on pentobarbital hypnosis as diminished when it was diluted with olive oil, but was markedly enhanced when diluted with dimethysusoxide (DMSO) before injection. Three local applications of methylchloroform )1:1 dilution with DMSO) had an effect similar to that of inhalation on pentobarbital hypnosis.

Cellular and regional localization of pentobarbital-2-14C by radioautography of selected areas of mouse brain at loss and return of withdrawal response.

Regional and cellular distribution of pentobarbital-14C in mouse brain was determined by frozen-section radioautographic methods. The mice were studied at the times of loss (WRL) and return (WRR) of withdrawal response following a single intravenous dose of either 40 or 50 mg/kg body weight. At WRL, grey matter areas had higher concentrations of pentobarbital-2-14C than white matter. At WRR grey matter concentrations were not altered, but white matter areas were now similar to the grey. At WRL pentobarbital concentration was 55 per cent higher in large pyramidal cells in the parietal cortex than in surrounding neuropil. At WRL hippocampal pyramidal cell bodies (stratum pyramidalis) and glial cells in corpus callosum had pentobarbital levels similar to that of surrounding neuropil. Levels in the neuropil of these three areas were higher at WRR than at WRL. Lipid-rich compartments had higher pentobarbital concentrations at WRR than at WRL. The results suggest that return of consciousness after pentobarbital anesthesia is associated with intracerebral redistribution of pentobarbital even while there is continuing uptake into brain. (Key words: Brain, pentobarbital uptake; hypnotics, barbiturates, pentobarbital; pharmacokinetics, pentobarbital uptake.).