ABSTRACT
Tuberculosis (TB) caused by Mycobacterium tuberculosis (M. tuberculosis) infection remains a major public health problem of global concern, largely due to antibiotics resistance, persistence and immune evasion. Sphingolipid bioactive molecules are involved in several important pathophysiological processes. Sphingosine-1-phosphate is a key product of sphingolipid metabolism, and can play a role in two manners: autocrine and/or paracrine. Sphingosine-1-phosphate regulates T cells and a variety of antigen-presenting cells during M. tuberculosis infection, promotes antigen processing and expression in monocytes, is involved in the maturation of phagolysosome, regulates Ca2+ homeostasis, participates in the autophagy of macrophages, inhibits the survival and proliferation of M. tuberculosis within host cells, and effectively reduces the necrosis of the mouse lungs infected by M. tuberculosis. Injection of 20 nmol per mouse sphingosine-1-phosphate inhibited up to 47% of mycobacterial growth in the lung and spleen of mice infected by M. tuberculosis. In this paper, sphingosine-1-phosphate, its receptors and regulatory network were reviewed, and the specific mechanism of sphingosine-1-phosphate inhibiting the survival of M. tuberculosis-infected host cells was elaborated. This will provide novel insights into the new targets for tuberculosis prevention and treatment.
ABSTRACT
<p><b>OBJECTIVE</b>To study a feasible method of measuring right ventricular pressure by catheterization in mice.</p><p><b>METHODS</b>Measuring the right ventricular pressure and the pulmonary artery pressure by homemade PE pipe through venous cannula in external jugular vein, using catheterization in mice with powerlab multimodal biometric signal recording system.</p><p><b>RESULTS</b>Forty-six out of 51 mice were experimented with this method smoothly and got a total success rate of 90.2%. Thirty of 33 normal mice and 16 of 18 mice with pulmonary arterial hypertension (PAH) were catheterized successfully. The right ventricular pressure were as follow: systolic blood pressure: (23.4 +/- 5.7) mmHg in normal group vs (32.2 +/- 2.8) mmHg in mice with PAH, diastolic blood pressure: (3.7 +/- 2.6) mmHg vs (3.8 +/- 2.0) mmHg, mean pressure: (12.0 +/- 3.7) mmHg vs (14.9 +/- 2.3) mmHg. After autopsy for those 5 failed cases, we found that 2 cases were into the inferior vena cava, another 2 cases pierced the right auricle and the last one punctured the axillary vein into the chest wall.</p><p><b>CONCLUSION</b>Measuring the right ventricular pressure through venous cannula in external jugular vein with homemade PE pipe in mice gets not only a high success rate but also help to save time. Moreover, this method can be popularized easily. It is a good and feasible method for measuring right ventricular pressure in mice.</p>