Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. It is abundant in marsh gas, livestock rumination, and combustible ice. Little is known about the use of methane in human disease treatment. Current research indicates that methane is useful for treating several diseases including ischemia and reperfusion injury, and inflammatory diseases. The mechanisms underlying the protective effects of methane appear primarily to involve anti-oxidation, anti-inflammation, and anti-apoptosis. In this review, we describe the beneficial effects of methane on different diseases, summarize possible mechanisms by which methane may act in these conditions, and discuss the purpose of methane production in hypoxic conditions. Then we propose several promising directions for the future research.
Antioxidants/pharmacology* ; Apoptosis/drug effects* ; Humans ; Inflammation/drug therapy* ; Ischemia/drug therapy* ; Methane/therapeutic use* ; Reperfusion Injury/drug therapy*

The effect of tea saponins (TS) on rumen fermentation and methane emission was examined using an in vitro gas production technique named Reading Pressure Technique. Three levels of TS addition (0, 0.2, 0.4 mg/ml) were evaluated in the faunated and defaunated rumen fluid. Compared to the control, TS addition decreased the 24 h gas production in the faunated rumen fluid, but had a minor effect on gas yield in the defaunated rumen fluid. The TS significantly reduced methane production in vitro. In the faunated rumen fluid, 0.2 or 0.4 mg/ml TS decreased the 24 h methane emission by 12.7% or 14.0%, respectively. Rumen fluid pH value was affected neither by TS addition nor by defaunation. The TS addition had only minor effects on volatile fatty acids, but the yield and pattern of volatile fatty acids were greatly affected by defaunation. While the molar proportion of acetate was not affected by defaunation, the propionate was significantly increased and the butyrate significantly decreased. Ammonia-N concentration and microbial protein yield were influenced by TS inclusion and defaunation. Inclusion of 0.4 mg/ml TS increased the microbial protein mass by 18.4% and 13.8% and decreased the ammonia-N concentration by 8.3% and 19.6% in the faunated and defaunated rumen fluid, respectively. Protozoa counts were significantly reduced by TS inclusion. The current study demonstrated the beneficial effect of TS on methane production and rumen fermentation, and indicated that this may be due to the effect of the associated depression on protozoa counts.
Animals ; Camellia sinensis ; metabolism ; Eukaryota ; drug effects ; physiology ; Fermentation ; drug effects ; Gastrointestinal Contents ; drug effects ; microbiology ; In Vitro Techniques ; Methane ; metabolism ; Plant Extracts ; pharmacology ; Rumen ; metabolism ; microbiology ; Saponins ; pharmacology ; Seeds ; metabolism ; Sheep ; Tea ; chemistry

Using a fluidized bed as immobilization system, mixed culture methanotrophic attached-films were developed on diatomite particles. The Methane Monooxygenase (MMO) activity was found to increase obviously as soon as the lag phase ended. Greater than 90% of the MMO activity in the bed was attached. Biofilm concentration of 3.3-3.7 mg dry weight cell/g DS was observed. Batch experiments were performed to explore the possibility of producing epoxypropane by a cooxidation process. The effect of methane on the oxidation of propene to epoxypropane and the effect of propene on the growth of methanotroph were also studied. In continuous experiments, optimum mixed gaseous substrates (methane: 35%; propene: 20%; oxygen: 45%) were continuously circulated through the fluidized bed reactor to remove product. Initial epoxypropane productivity was 110-150 mumol/d. The bioreactor operated continuously for 25 d without obvious loss of epoxypropane productivity.
Adhesins, Bacterial ; physiology ; Biofilms ; growth & development ; Bioreactors ; microbiology ; Cells, Immobilized ; drug effects ; enzymology ; microbiology ; Epoxy Compounds ; metabolism ; Methane ; metabolism ; pharmacology ; Methylococcaceae ; drug effects ; enzymology ; growth & development ; Methylosinus ; drug effects ; enzymology ; growth & development ; Oxidation-Reduction ; Oxygenases ; metabolism ; Propane ; metabolism ; pharmacology

BACKGROUND: Asthma is a common cause of breathing difficulty in children and adults, and is characterized by chronic airway inflammation that is poorly controlled by available treatments. This results in severe disability and applies a huge burden to the public health system. Methane has been demonstrated to function as a therapeutic agent in many diseases. The aim of the present study was to explore the effect of methane-rich saline (MRS) on the pathophysiology of a mouse model of asthma and its underlying mechanism. METHODS: A murine model of ovalbumin (OVA)-induced allergic asthma was applied in this study. Mice were divided into three groups: a control group, an OVA group, and OVA-induced asthmatic mice treated with MRS as the third group. Lung resistance index (RI) and dynamic compliance (Cdyn) were measured to determine airway hyper-responsiveness (AHR). Haematoxylin and eosin (H&E) staining was performed and scored to show histopathological changes. Cell counts of bronchoalveolar lavage fluid (BALF) were recorded. Cytokines interleukin (IL)-4, IL-5, IL-13, tumor necrosis factor α (TNF-α), and C-X-C motif chemokine ligand 15 (CXCL15) from BALF and serum were measured by enzyme-linked immunosorbent assay (ELISA). The oxidative stress indexes, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), myeloperoxidase (MPO), and 8-hydroxydeoxyguanosine (8-OHdG), were determined using commercial kits. Apoptosis was evaluated by western blot, quantitative real-time polymerase chain reaction (qRT-PCR), and biochemical examination. RESULTS: MRS administration reversed the OVA-induced AHR, attenuated the pathological inflammatory infiltration, and decreased the cytokines IL-4, IL-5, IL-13, TNF-α, and CXCL15 in serum and BALF. Moreover, following MRS administration, the oxidative stress was alleviated as indicated by decreased MDA, MPO, and 8-OHdG, and elevated SOD and GSH. In addition, MRS exhibited an anti-apoptotic effect in this model, protecting epithelial cells from damage. CONCLUSIONS Methane improves pulmonary function and decreases infiltrative inflammatory cells in the allergic asthmatic mouse model. This may be associated with its anti-inflammatory, antioxidative, and anti-apoptotic properties.
Animals ; Apoptosis/drug effects* ; Asthma/metabolism* ; Bronchial Hyperreactivity/drug therapy* ; Cytokines/analysis* ; Female ; Inflammation/prevention & control* ; Methane/pharmacology* ; Mice ; Mice, Inbred BALB C ; Oxidative Stress/drug effects* ; Saline Solution

According to the structure-activity relationships (SARs) of modafinil, a therapeutic drug of hypnolepsy, we designed and synthesized two series of compounds 2-[(diphenylmethane)sulfinyl] acetamides and 2-[(diphenylmethyl)thio] acetamides, and measured their biological activities. The target compounds (6a-6o) were synthesized beginning with diphenyl carbinol by substitution, oxidation, acylation and so on. Their structures were confirmed by ESI-MS, 1H NMR and elemental analysis. The central stimulatory effects of the target compounds were determined by the independent activity assay on mice. Compounds 6c, 6f and 6n have considerable activities, while the central stimulative effect of 6h is slightly better than the positive control modafinil.
Acetamides ; chemical synthesis ; chemistry ; pharmacology ; Animals ; Behavior, Animal ; drug effects ; Benzhydryl Compounds ; chemistry ; pharmacology ; Biphenyl Compounds ; chemical synthesis ; chemistry ; pharmacology ; Methane ; chemical synthesis ; chemistry ; pharmacology ; Mice ; Mice, Inbred ICR ; Random Allocation ; Structure-Activity Relationship ; Wakefulness-Promoting Agents ; chemical synthesis ; chemistry ; pharmacology