Hyperbaric oxygen treatment improves pancreatic ß­cell function and hepatic gluconeogenesis in STZ­induced type­2 diabetes mellitus model mice.

Type­2 diabetes mellitus (T2DM) causes several complications that affect the quality of life and life span of patients. Hyperbaric oxygen therapy (HBOT) has been used to successfully treat several diseases, including carbon monoxide poisoning, ischemia, infections and diabetic foot ulcer, and increases insulin sensitivity in T2DM. The present study aimed to determine the effect of HBOT on ß­cell function and hepatic gluconeogenesis in streptozotocin (STZ)­induced type­2 diabetic mice. To establish a T2DM model, 7­week­old male C57BL/6J mice were fed a high­fat diet (HFD) and injected once daily with low­dose STZ for 3 days after 1­week HFD feeding. At the 14th week, HFD+HBOT and T2DM+HBOT groups received 1­h HBOT (2 ATA; 100% pure O2) daily from 5:00 to 6:00 p.m. for 7 days. The HFD and T2DM groups were maintained under normobaric oxygen conditions and used as controls. During HBOT, the 12­h nocturnal food intake and body weight were measured daily. Moreover, blood glucose was measured by using a tail vein prick and a glucometer. After the final HBO treatment, all mice were sacrificed to conduct molecular biology experiments. Fasting insulin levels of blood samples of sacrificed mice were measured by an ultrasensitive ELISA kit. Pancreas and liver tissues were stained with hematoxylin and eosin, while immunohistochemistry was performed to determine the effects of HBOT on insulin resistance. TUNEL was used to determine the effects of HBOT on ß­cell apoptosis, and immunoblotting was conducted to determine the ß­cell apoptosis pathway. HBOT notably reduced fasting blood glucose and improved insulin sensitivity in T2DM mice. After HBOT, ß­cell area and ß­cell mass in T2DM mice were significantly increased. HBOT significantly decreased the ß­cell apoptotic rate in T2DM mice via the pancreatic Bcl­2/caspase­3/poly(ADP­ribose) polymerase (PARP) apoptosis pathway. Moreover, HBOT improved the morphology of the liver tissue and increased hepatic glycogen storage in T2DM mice. These findings suggested that HBOT ameliorated the insulin sensitivity of T2DM mice by decreasing the ß­cell apoptotic rate via the pancreatic Bcl­2/caspase­3/PARP apoptosis pathway.

Hyperbaric oxygen therapy mobilized circulating stem cells and improved delayed encephalopathy after acute carbon monoxide poisoning with up-regulation of brain-derived neurotrophic factor.

Background Delayed encephalopathy (DE) is the most severe complication after acute carbon monoxide (CO) poisoning, which seriously affects the outcome of patients and leads to a high disability rate. Prior studies have shown that hyperbaric oxygen (HBO2) therapy is therapeutic for DE due to reducing immune-mediated neuropathology and thus improving cognitive performance. Methods In our present perspective study, five DE patients were treated regularly with HBO2 therapy. The mini-mental state examination (MMSE) and Barthel index (BI) were intermittently collected during their hospitalization for mental and physical status evaluation, the peripheral bloods were serially sampled to determine the concentration changes of circulating stem cells, as well as corresponding BDNF and neural markers. Results MMSE and BI showed series of improvements after multiple HBO2 therapies. The CD34+/CD90+ and CD34+/CD133+ dual positive cells, which were categorized as circulating stem cells, were observed an overall up-regulation since the beginning of the DE onset upon the application of HBO2 therapy. Characteristic neurotrophin BDNF, neural markers such as nestin and synaptophysin (SYP) were also up-regulated after exposure of HBO2. Conclusion The application of HBO2 therapy is of significance in improving the cognition of DE patients, along with mobilized circulating stem cells. We primarily infer that the CD34+/CD90+ and CD34+/CD133+ cells were mobilized by HBO2 exposure and have played a positive role in cognition improvement on DE patients by up-regulation of BDNF, nestin and SYP. The altering amount of circulating stem cells mobilized in peripheral blood could be a potential marker on predicting the outcome of DE.

Ghrelin system is involved in improvements in glucose metabolism mediated by hyperbaric oxygen treatment in a streptozotocin­induced type 1 diabetes mouse model.

Type 1 diabetes mellitus (T1DM) is an autoimmune disorder for which the only effective therapy is insulin replacement. Hyperbaric oxygen (HBO) therapy has demonstrated potential in improving hyperglycemia and as a treatment option for T1DM. Ghrelin and HBO have been previously reported to exert proliferative, anti­apoptotic and anti­inflammatory effects in pancreatic cells. The present study investigated the mechanism underlying HBO­ and ghrelin system­mediated regulation of glucose metabolism. Male C57BL/6 mice were intraperitoneally injected with streptozotocin (STZ; 150 mg/kg) to induce T1DM before the diabetic mice were randomly assigned into the T1DM and T1DM + HBO groups. Mice in the T1DM + HBO group received HBO (1 h; 100% oxygen; 2 atmospheres absolute) daily for 2 weeks. Significantly lower blood glucose levels and food intake were observed in mice in the T1DM + HBO group. Following HBO treatment, islet ß­cell area were increased whereas those of α­cell were decreased in the pancreas. In addition, greater hepatic glycogen storage in liver was observed, which coincided with higher pancreatic glucose transporter 2 (GLUT2) expression levels and reduced hepatic GLUT2 membrane trafficking. There were also substantially higher total plasma ghrelin concentrations and gastric ghrelin­O­acyl transferase (GOAT) expression levels in mice in the T1DM + HBO group. HBO treatment also abolished reductions in pancreatic GOAT expression levels in T1DM mice. Additionally, hepatic growth hormone secretagogue receptor­1a levels were found to be lower in mice in the T1DM + HBO group compared with those in the T1DM group. These results suggest that HBO administration improved glucose metabolism in a STZ­induced T1DM mouse model. The underlying mechanism involves improved insulin­release, glucose­sensing and regulation of hepatic glycogen storage, an observation that was also likely dependent on the ghrelin signalling system.

Hyperbaric Oxygen Ameliorates Insulin Sensitivity by Increasing GLUT4 Expression in Skeletal Muscle and Stimulating UCP1 in Brown Adipose Tissue in T2DM Mice.

Hyperbaric oxygen (HBO) therapy is a treatment modality useful for diseases. Hypoxia could stimulate the induction of insulin resistance. Therefore, we sought to determine whether hyperbaric oxygen would ameliorate insulin sensitivity by promoting glucose transporter type 4 (GLUT4) expression in muscle and by stimulating UCP1 in brown adipose tissue (BAT) in a streptozocin (STZ)-induced type 2 diabetes mellitus (T2DM) mouse model. Male C57BL/6J mice were treated three times with low-dose of streptozocin (60 mg/kg, i.p.) and were fed with high-fat diets (HFD) to establish the T2DM model. HBO was administered daily as 100% oxygen at 2.0 atmosphere absolute (ATA) for 1 h for a week. We found that HBO significantly reduced blood glucose levels and attenuated insulin resistance in T2DM mice. HBO modulated food intake by influencing the activity of neuropeptide Y (NPY)-positive neurons in the arcuate nucleus (Arc). HBO treatment increased GLUT4 amount and level of phosphorylated Akt (p-Akt) in muscles of T2DM mice whereas this treatment stimulated the phosphorylation of AMPK in muscles of both T2DM and HFD mice. The morphological staining of BAT and the increased expression of uncoupling of protein 1 (UCP1) demonstrated the promotion of metabolism after HBO treatment. These findings suggest that HBO ameliorates insulin sensitivity of T2DM mice by stimulating the Akt signaling pathway and by promoting GLUT4 expression in muscle, and by increasing UCP1 expression in BAT.

Hyperbaric oxygen suppresses growth of Klebsiella pneumoniae and enhances effect of tigecycline in vitro.

OBJECTIVES: (1) To examine whether hyperbaric oxygen (HBO2) will inhibit growth of multidrug-resistant Klebsiella pneumoniae (MDR-K. pneumoniae) and extensively drug-resistant Klebsiella pneumoniae (XDR-K. pneumoniae); (2) To determine whether the effect of tigecycline on XDR-K. pneumoniae will be enhanced by HBO2. METHODS: The effects of 1.5 hours of treatment with normoxia (21% O2, 1 atmosphere absolute/ATA) or HBO2 (100% O2, 2 ATA) on bacterial counts of eight isolates of MDR-K. pneumoniae and eight isolates of XDR-K. pneumoniae were studied. The effects of five hours of treatment with normoxia (21% O2, 1 ATA), tigecycline (21% O2, 1 ATA), HBO2 (100% O2, 3 ATA) or HBO2 + tigecycline (100% O2, 3 ATA) on proliferation of 10 isolates of XDR-K. pneumoniae were investigated. RESULTS: HBO2 at 100% O2, 2 ATA, 1.5 hours suppressed growth of MDR-K. pneumoniae but had no effect on XDR-K. pneumoniae. HBO2 at 100% O2, 3 ATA, five hours enhanced the effects of tigecycline on XDR-K. pneumoniae. CONCLUSIONS: HBO2 in combination with or without tigecycline can be used to eliminate K. pneumoniae in vitro, and such treatment may be beneficial for patients with infections caused by K. pneumoniae.

Effect of Electroacupuncture on Transcutaneous Oxygen Partial Pressure During Hyperbaric Oxygen Therapy in Healthy Individuals.

CONTEXT: The goal of hyperbaric oxygen therapy (HBOT) is to increase the oxygen (O2) supply to the body significantly. Because of the toxic side effects and complications of hyperbaric oxygen (HBO2), the environmental pressure and treatment time must be restricted. The research team hypothesized that other therapies administered during HBOT could safely improve the value of the arterial oxygen partial pressure (PaO2) during HBOT and improve its therapeutic effect. OBJECTIVE: The study intended to investigate whether electroacupuncture (EA) while receiving HBOT had a greater effect for healthy individuals than HBOT or EA alone or EA combined with normobaric pure oxygen (pure O2). DESIGN: The research team designed a randomized, controlled trial. SETTING: The study was performed in the Department of Hyperbaric Medicine at the No. 401 Hospital of the People's Liberation Army in Qingdao, China. PARTICIPANTS: A total of 81 volunteers were recruited. After thorough physical examination and laboratory testing, 21 volunteers were excluded from the study. Participants included 60 healthy volunteers. INTERVENTION: Participants were randomly assigned to 1 of 4 groups of 15 participants each: (1) an HBOT group, (2) an EA group, (3) an EA During HBOT group, and (4) an EA Combined With Pure O2group. OUTCOME MEASURES: Because at the current technology level a blood gas analyzer cannot test PaO2during HBOT, transcutaneous oxygen partial pressure (PtcO2) of the participants was tested instead. Before, during, and after EA, variations in PtcO2were monitored in each group. RESULTS: For the EA During HBOT group, (1) the increase in PtcO2during EA was significantly greater than that observed for the other 3 groups (P > .05). CONCLUSIONS: The EA During HBOT method provided improvements in the efficacy, safety, and tolerability of HBOT, and the study's results partially demonstrated the accuracy of the research team's hypothesis that EA therapy applied during HBOT could safely improve the value of PtcO2(PaO2) during HBOT and produce a greater therapeutic effect.

Analysis of medicine consumption in peacekeeping level II hospitals.

BACKGROUND: The peacekeeping military units of contributing countries are unfamiliar with the conditions prevailing in foreign mission areas and therefore have difficulties with medical supplies storage. AIM: The aim of this study is to provide reasonable and practical guidance on the maintenance of medical supplies in the peacekeeping military units of contributing countries. MATERIALS AND METHODS: A total of 1,972 prescriptions were received by the pharmacy in the peacekeeping level II hospital in the Republic of Sudan from February to July of 2009 including a total of 186 drug categories and 17,713 minimum packing units. Pairwise comparison was performed using the c2 test. When the total number of samples was smaller than 40, the Fisher's exact test was adopted for pairwise comparison. RESULTS: The majority of the consumed medicines mainly belonged to 6 categories, including specialty drugs, anti-microbial drugs, Chinese patent medicines, gastrointestinal drugs, central nervous system drugs, and drugs regulating fluids, electrolytes, and acid-base balance. Altogether, the drugs in the 6 categories accounted for 74% of all consumed medicines that were divided into a total of 20 categories. CONCLUSIONS: Medicine consumption in peacekeeping level II hospitals is unique, therefore the drugs used in military medical facilities should be prepared according to their actual needs in the area of peacekeeping operations.

Effects of positive end-expiratory pressure on intracranial pressure in mechanically ventilated dogs under hyperbaric oxygenation.

Mechanical ventilation with positive end-expiratory pressure (PEEP) has been advocated as an essential life support for critical patients. However, its side effect, which is demonstrated by an elevation of intracranial pressure (ICP) under normobaric (NBO2) conditions, is potentially detrimental to patients. Hyperbaric oxygen (HBO2) therapy, on the other hand, is frequently applied for the same group of patients, and its efficacy is shown by maintaining a higher PaO2 and a reduced ICP. Our study investigated the effect of HBO2 and NBO2 on ICP with or without PEEP ventilation on healthy dogs by comparing cerebrospinal fluid pressure (CSFP) and concluded that the elevation of PEEP resulted in a significant increase of ICP (CSFP) under both conditions (p < 0.05). HBO2 leads to a lower ICP increase compared to the NBO2 group. Under the same level of PEEP, the joint use of PEEP and HBO2 is safe and highly practical in clinical medicine.

The relevance of magnetic resonance imaging in spinal cord decompression sickness: a survey of seven cases.

To investigate the magnetic resonance imaging (MRI) features of spinal cord decompression sickness (DCS) on compressed-air divers, we hereby report seven cases diagnosed with spinal cord DCS. Only two patients out of seven showed positive MRI findings: A detailed case report will be provided on each. In one of the cases, the MRI revealed extensive high signal within the central gray matter of the spinal cord. The other one showed patchy high signal on T2-weighted images as well as diffusion-weighted images (DWI) in the dorsal column white matter of the spinal cord. The findings in our collective suggest that the MRI focused on the spinal cord is not always appropriate for obtaining a quick diagnosis. The discrepancy between MRI findings and clinical evolution leads to the conclusion that MRI focused on the spinal cord does not always correlate with neurological improvement. Decision for hyperbaric oxygen (HBO2) treatment should not be based primarily on MRI findings.