2.Effects of Streptococcus pneumoniae on the ultrastructure of alveolar epithelial cells type Ⅱ in the lung tissues of mice and children.
Lin-Hua SHU ; Yun-Xiao SHANG ; Fu-Hui ZHANG ; Han ZHANG ; Xiao-Xue MA ; Nan YANG ; Wan-Jie HUANG
Chinese Journal of Contemporary Pediatrics 2011;13(4):336-339
OBJECTIVETo explore the possible mechanisms of lung necrosis by examining the effects of Streptoccus pneumoniae (S.p) on the ultrastructure of alveolar epithelial cells type Ⅱ(AEC-Ⅱ) in the lung tissues of mice and children.
METHODSThe suspended solutions of S.p strains cultured from the blood of a child with pneumococcal necrotizing pneumonia (PNP) (0.3 mL, CFU: 1×108/L) were instilled into the trachea of pathogen-free mice to prepare PNP model. The same amount of normal saline was given for the control group (10 mice). The samples (1 mm3) from the lower lobe of right lung of the mice were obtained 92 hrs later and fixed in 2.5% glutaraldehyde. Normal and abnormal lung tissues (1 mm3) were obtained while operation for the left lower lobe pulmonary cavity excision in the child with PNP. The specimens were fixed in 2.5% glutaraldehyde and stored at 4℃. A transmission electron microscope was employed for the examination of the ultrastructure of AEC-Ⅱ in the lung tissues.
RESULTSQuantitative reduction and exfoliation of microvilli in S.p-infected AEC-Ⅱ were observed in both mice and this child compared with the control. Enlarged size, enhanced evacuation and reduced density of the lamellar bodies were also presented. The number of mitochondria was obviously reduced. The nucleolus chromatin concentrated and showed an inhomogeneous distribution.
CONCLUSIONSS.p infection results in comparable damage to the ultrastructure of AEC-Ⅱ in mice and children that may represent one of the primary causes responsible for S.p-induced lung tissue necrosis.
Animals ; Child ; Epithelial Cells ; ultrastructure ; Female ; Humans ; Mice ; Pneumonia, Pneumococcal ; pathology ; Pulmonary Alveoli ; ultrastructure
3.Modified Si-Miao-San ameliorates pancreatic B cell dysfunction by inhibition of reactive oxygen species-associated inflammation through AMP-kinase activation.
Shu-Wan SHANG ; Jiang-Lin YANG ; Fang HUANG ; Kang LIU ; Bao-Lin LIU
Chinese Journal of Natural Medicines (English Ed.) 2014;12(5):351-360
AIM:
To observe the effect of modified Si-Miao-San (mSMS) on advanced glycation end products (AGEs)-induced pancreatic B cell dysfunction, as well as examining the underlying mechanisms.
METHOD:
Pancreatic B cells (INS-1) were stimulated with advanced glycation end products (AGEs, 200 μg·mL(-1)) for 24 h to produce dysfunction in pancreatic B cells and the effects of mSMS observed on insulin secretion, NF-κB (p65) phosphorylation, reactive oxygen species (ROS) production, mitochondria membrane potential (Δψm), cell apoptosis, phosphorylation of AMP-kinase (AMPK), and caspase 3 activity.
RESULTS:
The AGEs challenge resulted in increased basal insulin secretion, but decreased insulin secretion in response to high glucose, whereas this situation was reversed by mSMS treatment. AGEs stimulation induced NF-κB (p65) phosphorylation and reactive oxygen species (ROS) production, as well as Δψm collapse and cell apoptosis. mSMS inhibited ROS production and inhibited NF-κB activation by attenuating p65 phosphorylation. Meanwhile, AGEs-induced Δψm collapse and cell apoptosis were also reversed by mSMS treatment. Compound C, an inhibitor of AMP-Kinase (AMPK), abolished the beneficial effects of mSMS on the regulation of B cell function, indicating the involvement of AMPK.
CONCLUSION
mSMS ameliorated AGEs-induced B cell dysfunction by suppressing ROS-associated inflammation, and this action was related to its beneficial regulation of AMPK activity.
AMP-Activated Protein Kinases
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genetics
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metabolism
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Animals
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Apoptosis
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drug effects
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Cell Line, Tumor
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Drugs, Chinese Herbal
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pharmacology
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Glucose
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metabolism
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Glycation End Products, Advanced
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metabolism
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Humans
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Inflammation
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drug therapy
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enzymology
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genetics
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metabolism
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Insulin-Secreting Cells
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cytology
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drug effects
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enzymology
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metabolism
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Phosphorylation
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Rats
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Reactive Oxygen Species
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metabolism