Adenovirus-mediated osteoprotegerin ameliorates cartilage destruction by inhibiting proteoglycan loss and chondrocyte apoptosis in rats with collagen-induced arthritis.

Our aim is to elucidate the effects of osteoproteogerin (OPG) on cartilage destruction in rats as a model of collagen-induced arthritis (CIA). To establish the CIA model, Sprague Dawley rats were injected with bovine type II collagen solution subcutaneously via the tails. Adenovirus-mediated OPG (Ad-OPG) was then injected intra-articularly either at the beginning of CIA (early OPG treatment) or one week after CIA establishment (late OPG treatment); vehicle or Ad-green fluorescent protein were injected as controls. The rats were killed 4 weeks after treatment. Ankle-joint sections were obtained for histology. Serum samples were collected for enzyme-linked immunosorbent assay. Safranin O staining showed that proteoglycan loss was inhibited in the early and late Ad-OPG groups. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining revealed that both early and late Ad-OPG treatments significantly prevented chondrocyte apoptosis in CIA rats. Furthermore, disintegrin and metalloproteinase with thrombospondin motif-5 expression decreased remarkably in the early and late OPG treatment groups. However, the cartilage destruction score, cartilage oligomeric matrix protein level and caspase-3 expression were only decreased in the early Ad-OPG treatment group. Additionally, ankle-joint swelling and the interleukin-1ß expression level in CIA rats were not notably altered by Ad-OPG treatment. Taken together, our results suggest that early Ad-OPG treatment has potent protective effects against cartilage destruction during rheumatoid arthritis progression, mainly by reducing proteoglycan loss and chondrocyte apoptosis.

[Formaldehyde inhalation may damage olfactory bulb and hippocampus in rats].

OBJECTIVE: To investigate the effects of formaldehyde inhalation on the morphological damage, and Glu, GABA and NOS contents in olfactory bulb and hippocampus of rats. METHODS: Twenty SD rats were equally divided into two groups: rats in the control group inhaled fresh air, while the animals in experimental group were exposed to the air containing formaldehyde (12.5 mg/m(3), 4 h/d) for 7 days. Then rats were sacrificed and frozen sections of olfactory bulb and hippocampus were prepared. The morphological changes were examined and the Glu, GABA and NOS contents were detected using Nissl-staining, immunohistochemistry and Western blot, respectively. RESULT: Compared with the control group, there was a significant confusion and shrink of neuron morphology in experimental group, the number and staining intensity of Glu and NOS positive cells and protein contents were reduced. The protein expression of GABA was also decreased in the formaldehyde group. CONCLUSION: Formaldehyde inhalation can cause a severe morphological damage of olfactory bulb and hippocampus in SD rats,which may further impair memory and learning ability through the reduction of Glu, GABA and NOS expression.

[Effects of Eucalyptus grandis leaf litter at its early stage of decomposition on the growth and photosynthetic characteristics of Cichorium intybus].

From March to May, 2010, a pot experiment was conducted to investigate the effects of Eucalyptus grandis leaf litter at its early stage of decomposition on the growth and photosynthetic characteristics of Cichorium intybus. Four treatments with different application rate of the leaf litter, i.e., 0 g x pot(-1) (CK), 30 g x pot(-1) (A1), 60 g x pot(-1) (A2), and 90 g x pot(-1) (A3), were installed. Each pot contained 12 kg soil mixed with the leaf litter, and then, C. intybus was sown. The growth indicators of the C. intybus were measured at the 30, 45, 60, and 75 d after sowing, and the photosynthetic characteristics of the C. intybus in treatment A3 were studied after the seedlings third leaf fully expanded. At each measured time, the biomass accumulation and leaf area growth of C. intybus in treatments A1, A2, and A3 were inhibited significantly. At the early stage of the leaf litter decomposition, the synthesis of photosynthetic pigments of the C. intybus seedlings was inhibited significantly, and the inhibition effect was getting stronger with the increasing amount of the leaf litter addition. The diurnal change of the seedlings photosynthetic rate in all treatments showed a bimodal curve with midday depression, the stomatal conductance and water use efficiency had the same variation trend with the net photosynthetic rate, and the total diurnal photosynthesis decreased in the order of CK > A1 > A2 > A3. The GC-MS analysis showed there were 33 kinds of small molecule compounds released gradually with the decomposition of the leaf litter, among which, allelopathic substance terpenoid dominated.