Effect of alisol A on cerebral ischemia reperfusion injury by protecting blood brain barrier and its mechanism / 中国药理学通报

Aim To investigate whether alisol A (AA) could improve the blood brain barrier (BBB) mediated cortex cerebral ischemia-repeifusion injury (CIRI) by inhibiting matrix metalloproteinase 9 (MMP-9). Methods The global cerebral ischemia- reperfusion (GCI/R) model in mice was established, and the AA was intragastric injected subsequently for seven days. The modified neurological severity scores (mNSS), open field test and Y-maze test were applied to detect neurological function. Magnetic resonance spectroscopy (MRS) was used to detect relevant neu- rosubstance metabolism in cortex of mice. Transmission electron microscope (TEM) was employed to observe the ultrastructure of BBB in cortex. Western blot and immunohistochemistry were used to detect the MMP-9 level in cortex. The binding possibility of A A and MMP-9 was determined by molecular docking. Results Compared with Sham group, mice in GCI/R group have an increased mNSS score but decreased at total distance and center distance to total distance ratio in open field test as well as alternation rate in Y-maze test (P<0.01). While mice in GCI/R + AA group have a decreased mNSS score but increased at total distance and center distance to total distance ratio in open field test as well as alternation rate in Y-maze test (P<0.01) compared with GCI/R group. MRS results found that in cortex of GCI/R group mice, the level of GABA and NAA significantly decreased while the Cho, mI and Tau level increased (P<0.01). Whereas in GCI/R + AA group mice, the GABA and NAA level increased and the Cho, ml and Tau decreased significantly (P<0.01). By TEM we observed that the basilemma of cerebral microvessels collapsed, the lumen narrowed, the endothelial cells were active and plasma membranes ruffled, gaps between cells were enlarged and tight junctions were damaged and the end feet of astrocytes were swollen in GCI/R group mice. While in GCI/R + AA group mice, the lumen was filled, plasma membranes of endothelial cells were smooth, tight junctions were complete and end feet of astrocytes were in normal condition. Western blot and immunohistochemistry both found that the MMP-9 level increased in GCI/R group mice (P < 0.01) and decreased in GCI/R + AA group mice (P < 0.05). Molecular docking proved the binding between aliso A and MMP9 through TYR-50 and ARG-106, and the binding energy was calculated as -6.24 kcal · mol

Functional Connectivity from Hypothalamus and Whole Brain Anisotropy in Patients with Dysphagia after Stroke: A Study with Magnetic Resonance Imaging / 中国康复理论与实践

Objective:To investigate the changes of the functional connectivity of hypothalamus and the whole brain anisotropy in patients with dysphagia after stroke using magnetic resonance imaging. Methods:From December, 2018 to December, 2019, 14 patients with dysphagia after stroke and 15 healthy controls matched in age, sex and dominant hemisphere were selected. The functional connections from bilateral hypothalamus were researched with resting-state functional nuclear magnetic resonance, and the correlation between functional connection and scores of Eating Assessment Tool-10 (EAT-10) was analyzed. Meanwhile, the whole brain white matter integrity was observed with diffusion tensor imaging, and the fraction anisotropy (FA) was compared. Results:Compared with the controls, the functional connections from left hypothalamus to left precentral gyrus, left postcentral gyrus, left marginal lobe, left parietal lobe and left occipital lobe decreased in the patients; while the functional connections to left thalamus, left midbrain and right occipital lobe increased; the functional connections from right hypothalamus to right precentral gyrus, bilateral marginal lobe, bilateral superior temporal gyrus and right parietal lobe decreased; the functional connection to bilateral parietal lobe and bilateral occipital lobe increased. There was negative correlation of EAT-10 scores to functional connection from left hypothalamus to left precentral gyrus (r = -0.595, P = 0.025) and left postcentral gyrus (r = -0.934, P < 0.001), and positive correlation to functional connections from left hypothalamus to left parietal lobe (r = 0.583, P = 0.028) and from right hypothalamus to left occipital lobe (r = 0.630, P = 0.016). Compared with the controls, FA decreased in bilateral precentral gyrus, bilateral postcentral gyrus, bilateral frontal lobe, bilateral parietal lobe, bilateral occipital lobe, bilateral caudate nucleus, bilateral thalamus, right medulla, right superior temporal gyrus, right pontine and left posterior cerebellar lobe in the patients; while FA increased in bilateral anterior lobe of cerebellum and right cingulate gyrus. Conclusion:The motor and sensory cortices are important for swallowing. Patients with dysphagia after stroke may spend more attention and visual compensation. Impairment of white matter is found in swallowing cortex, subcortical structure and brainstem swallowing center in patients with dysphagia after stroke.

X-ray dynamic observation of cervical degenerative disease induced by unbalanced dynamic and static forces in rats

Abstract Purpose: To investigate dynamically the X-ray appearance of cervical degenerative disease induced by unbalanced dynamic and static forces in rats. Methods: A total of 60 Sprague Dawley rats were randomized into test (n=45) and control (n=15) groups, which were randomly subdivided into the one-, three- and six-month post-operative groups. The test group included 10, 15 and 20 rats at the respective corresponding post-operative stage and the control group included five rats at each time-point. By excising cervicodorsal muscles, interspinous ligaments and supraspinous ligament of rats in the test group, the balance of dynamic and static forces on cervical vertebrae was disrupted to establish a rat model of cervical degeneration. Spinal X-ray images were acquired, and intervertebral disc space and intervertebral foramen size were measured at one, three and six months post-operation. The results were analyzed and compared among groups. Results: Cervical dynamic and static imbalance accelerated the appearance of cervical degenerative disease on X-ray. Conclusion: Cervical degenerative disease may be induced by unbalanced dynamic and static forces in rats.

Inhibition of tryptase release from human colon mast cells by histamine receptor antagonists.

The main objective of this study was to investigate the ability of histamine receptor antagonists to modulate tryptase release from human colon mast cells induced by histamine. Enzymatically dispersed cells from human colon were challenged with histamine in the absence or presence of the histamine receptor antagonists, and the tryptase release was determined. It was found that histamine induced tryptase release from colon mast cells was inhibited by up to approximately 61.5% and 24% by the H1 histamine receptor antagonist terfenadine and the H2 histamine receptor antagonist cimetidine, respectively, when histamine and its antagonists were added to cells at the same time. The H3 histamine receptor antagonist clobenpropit had no effect on histamine induced tryptase release from colon mast cells at all concentrations tested. Preincubation of terfenadine, cimetidine or clobenpropit with cells for 20 minutes before challenging with histamine did not enhance the ability of these antihistamines to inhibit histamine induced tryptase release. Apart from terfenadine at 100 microg/ml, the antagonists themselves did not stimulate tryptase release from colon mast cells following both 15 minutes and 35 minutes incubation periods. It was concluded that H1 and H2 histamine receptor antagonists were able to inhibit histamine induced tryptase release from colon mast cells. This not only added some new data to our hypothesis of self-amplification mechanisms of mast cell degranulation, but also suggested that combining these two types of antihistamine drugs could be useful for the treatment of inflammatory bowel disease (IBD).

Modulation of tryptase and histamine release from human lung mast cells by protease inhibitors.

Inhibition of IgE dependent histamine release from human mast cells by protease inhibitors has been observed in skin, tonsil and synovial tissues. However, little is known about the actions of protease inhibitors on tryptase release from human lung mast cells. We therefore examined the ability of protease inhibitors to modulate tryptase and histamine release from human lung mast cells. IgE dependent tryptase release from dispersed lung mast cells was inhibited to a maximum of approximately 53.8% and 44.5% by N-a-tosyl-L-lysine chloromethyl ketone (TLCK) and N-p-Tosyl-L-phenylalanine chloromethyl ketone (TPCK), respectively. A similar degree of inhibition of calcium ionophore A23187 (CI) induced tryptase release was also observed with these two inhibitors. Preincubation of TLCK or TPCK with the mast cells at 37 degrees C for 20 minutes before addition of anti-IgE or CI did not improve their ability to inhibit anti-IgE and CI induced tryptase release. At a concentration of 10 microg/ml, protamine inhibited anti-IgE or CI induced tryptase release; but at 100 microg/ml, it increased anti-IgE and CI induced release of tryptase from lung mast cells. A concentration dependent inhibition of anti-IgE and CI induced release of histamine from lung mast cells was also observed with TLCK, TPCK and protamine. The maximum inhibition of anti-IgE induced histamine release was approximately 40.7%, 40.2% and 33.4% with TLCK, TPCK and protamine, respectively. At the concentrations tested, TLCK and TPCK by themselves did not stimulate tryptase and histamine release from lung mast cells. A specific inhibitor of aminopeptidase, amastatin, had no effect on anti-IgE induced tryptase and histamine release and was used as control. In conclusion, it was demonstrated that protease inhibitors are able to inhibit IgE dependent tryptase and histamine release from human lung mast cells, which suggested that they could be developed to a novel class of anti-inflammatory drugs to treat allergic conditions in man.

Selectively enhanced sensitivity of bronchoalveolar lavage fluid (BALF) mast cells to IgE dependent stimulation in mild asthmatics.

The aim of this study is to investigate the histamine-releasing ability of mast cells from asthmatic bronchoalveolar lavage fluid (BALF). Following the measurement of the forced expiratory volume at the first second (FEV1), 29 mild asthmatics were included in the study and were subjected to fibreoptic bronchoscopy. The cells recovered from the BALF were challenged with anti-IgE, calcium ionophore A23187 (CI) or adenosine, and the released histamine was measured with an enzyme-linked chromogenic assay. Enzymatically dispersed mast cells from human lung or colon tissues were employed as control groups. The results showed that mast cells from BALF were at least 100 fold more sensitive to anti-IgE than those from lung or colon tissues. However, there was little difference between mast cells from BALF, lung or colon tissues in response to CI. Adenosine failed to stimulate histamine release from BALF mast cells. In conclusion, asthmatic BALF mast cells are much more sensitive to IgE-dependent stimulation than the non-IgE-dependent ones, indicating that mast cells may play a role in the pathogenesis of asthma.