Ginsenoside Rb1 Attenuates Isoflurane/surgery-induced Cognitive Dysfunction via Inhibiting Neuroinflammation and Oxidative Stress / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Anesthetic isoflurane plus surgery has been reported to induce cognitive impairment. The underlying mechanism and targeted intervention remain largely to be determined. Ginsenoside Rb1 was reported to be neuroprotective. We therefore set out to determine whether ginsenoside Rb1 can attenuate isoflurane/surgery-induced cognitive dysfunction via inhibiting neuroinflammation and oxidative stress.</p><p><b>METHODS</b>Five-months-old C57BL/6J female mice were treated with 1.4% isoflurane plus abdominal surgery for two hours. Sixty mg/kg ginsenoside Rb1 were given intraperitoneally from 7 days before surgery. Cognition of the mice were assessed by Barnes Maze. Levels of postsynaptic density-95 and synaptophysin in mice hippocampus were measured by Western blot. Levels of reactive oxygen species, tumor necrosis factor-α and interleukin-6 in mice hippocampus were measured by ELISA.</p><p><b>RESULTS</b>Here we show for the first time that the ginsenoside Rb1 treatment attenuated the isoflurane/surgery-induced cognitive impairment. Moreover, ginsenoside Rb1 attenuated the isoflurane/surgery-induced synapse dysfunction. Finally, ginsenoside Rb1 mitigated the isoflurane/surgery-induced elevation levels of reactive oxygen species, tumor necrosis factor-α and interleukin-6 in the mice hippocampus.</p><p><b>CONCLUSION</b>These results suggest that ginsenoside Rb1 may attenuate the isoflurane/surgery-induced cognitive impairment by inhibiting neuroinflammation and oxidative stress pending future studies.</p>

Ginsenoside Rg1 Attenuates Isoflurane-induced Caspase-3 Activation via Inhibiting Mitochondrial Dysfunction / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>The inhalation anesthetic isoflurane has been shown to induce mitochondrial dysfunction and caspase activation, which may lead to learning and memory impairment. Ginsenoside Rg1 is reported to be neuroprotective. We therefore set out to determine whether ginsenoside Rg1 can attenuate isoflurane-induced caspase activation via inhibiting mitochondrial dysfunction.</p><p><b>METHODS</b>We investigated the effects of ginsenoside Rg1 at concentrations of 12.5, 25, and 50 μmol/L and pretreatment times of 12 h and 24 h on isoflurane-induced caspase-3 activation in H4 naïve and stably transfected H4 human neuroglioma cells that express full-length human amyloid precursor protein (APP) (H4-APP cells). For mitochondrial dysfunction, we assessed mitochondrial permeability transition pore (mPTP) and adenosine-5'-triphosphate (ATP) levels. We employed Western blot analysis, chemiluminescence, and flowcytometry.</p><p><b>RESULTS</b>Here we show that pretreatment with 50 µmol/L ginsenoside Rg1 for 12 h attenuated isoflurane-induced caspase-3 activation and mitochondrial dysfunction in H4-APP cells, while pretreatment with 25 and 50 µmol/L ginsenoside Rg1 for 24 h attenuated isoflurane-induced caspase-3 activation and mitochondrial dysfunction in both H4 naïve and H4-APP cells.</p><p><b>CONCLUSION</b>These data suggest that ginsenoside Rg1 may ameliorate isoflurane-induced caspase-3 activation by inhibiting mitochondrial dysfunction. Pending further studies, these findings might recommend the use of ginsenoside Rg1 in preventing and treating isoflurane-induced neurotoxicity.</p>

Relationship between depth of anesthesia and effect-site concentration of propofol during induction with the target-controlled infusion technique in elderly patients / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>There are few studies to assess whether the effect-site concentration of propofol can predict anesthetic depth during the target-controlled infusion (TCI) induction in elderly patients. This study aimed to evaluate the relationship between effect-site concentration of propofol and depth of anesthesia during the TCI induction in elderly patients.</p><p><b>METHODS</b>Ninety patients (60 - 80 years) with an American Society of Anesthesiologists (ASA) physical status of 1 - 3, undergoing scheduled abdominal and thoracic surgery under general anesthesia were randomly allocated into one of three groups, Group S1, S2 and S3 (30 patients in each group). The patients in Group S1 received propofol with a target plasma concentration of 4.0 microg/ml; patients in Group S2 received propofol with an initial target plasma concentrations of 2.0 microg/ml that was raised to 4.0 microg/ml 3 minutes later; patients in Group S3 received an infused scheme of 3 steps; starting from a target plasma concentration of 2.0 microg/ml that was increased stepwised by 1 microg/ml until a target plasma concentration of 4.0 microg/ml was achieved, the interval between the two steps was 3 minutes. When an Observer's Assessment of Alertness/Sedation (OAA/S) score of 1 was achieved, remifentanil (effect-site concentration (Ce) of 4.0 ng/ml) and rocuronium 0.9 mg/kg were administered. Tracheal intubation was started 2 minutes after rocuronium injection. Changes of propofol Ce, blood pressure (BP), heart rate (HR), and bispectral index (BIS) were recorded.</p><p><b>RESULTS</b>When an OAA/S score of 1 was achieved, Ce of propofol were (1.7 +/- 0.4) microg/ml, (1.9 +/- 0.3) microg/ml, (1.9 +/- 0.4) microg/ml and the BIS values were 64 +/- 5, 65 +/- 8, and 62 +/- 8 in Groups S1, S2 and S3. Before intubation, Ce of propofol was (2.8 +/- 0.2) microg/ml, (2.8 +/- 0.3) microg/ml, (2.7 +/- 0.3) microg/ml, and the BIS values were 48 +/- 7, 51 +/- 7, and 47 +/- 5 in Groups S1, S2 and S3. By linear regression analysis, a significant correlation between Ce of propofol and BIS values was found (r = -0.580, P < 0.01). Systolic blood pressure (SBP) before intubation was significantly lower in Group S1 than in Groups S2 and S3. SBP and HR after intubation in the three groups were significantly increased when compared with pre-intubation values, but they did not exceed baseline values.</p><p><b>CONCLUSIONS</b>During the TCI induction, Ce of propofol with (1.9 +/- 0.3) microg/ml may make the elderly patients unconscious. When remifentanil with a Ce of 4.0 ng/ml is added a Ce of propofol with (2.8 +/- 0.3) microg/ml is suitable for intubation. The Ce of propofol has a close correlation with the BIS values. Also, a two-step TCI technique seems to be a more suitable method of anesthesia induction in elderly patients compared with the no-stepwise TCI technique and three-step TCI technique.</p>

Effect of propofol on hypoxic pulmonary vasoconstriction in rats / 中华麻醉学杂志

Objective To investigate the effect of propofol on hypoxic pulmonary vasoconstriction(HPV)and assess the underlying mechanism in rats.Methods Twenty male SD rats weighing 300-400 g were.anesthetizedwith intraperitoneal phenobarbital.Heart and lungs were removed after thoracotomy.Pulmonary.arterial rings 4 mmin length and 1.0-1.4 mm in diameter were prepared and suspended in Earl solution maintained at 37℃ with a pHof 7.40 and aerated with 20% O_2-5% CO_2-25% N_2.The rings were stimulated with phenylephrine(PE)10~(-6)mol?L~(-1) with different preloads(300,500,700,900,1 100 mg).The isometric tension of the arterial rings wasmeasured.The optimal preload was determined to be 900 mg which allowed best contractility.Hypoxia was inducedby aerating the solution with 95% N_2-5% CO_2 and the flow rate was adjusted to maintain PO_2 of the solution at40-20 mm Hg and pH at 7.40.HPV of the rings were recorded.Then propofol was added to achieve a finalconcentration of 1,3,10,30,100 ?mol?L~(-1) and HPV was again induced and the changes in HPV wererecorded.In addition the effects of propofol(10,30 ?mol?L~(-1))on vasoconstriction produced by KCI and PE werealso measured.Results The lower doses of propofol(10 ?mol?L~(-1))significantly inhibited HPV(P