Protective effect of intervention with cannabinoid type-2 receptor agonist JWH133 on pulmonary fibrosis in mice / 中华内科杂志

Objective: JWH133, a cannabinoid type 2 receptor agonist, was tested for its ability to protect mice from bleomycin-induced pulmonary fibrosis. Methods: By using a random number generator, 24 C57BL/6J male mice were randomly divided into the control group, model group, JWH133 intervention group, and JWH133+a cannabinoid type-2 receptor antagonist (AM630) inhibitor group, with 6 mice in each group. A mouse pulmonary fibrosis model was established by tracheal instillation of bleomycin (5 mg/kg). Starting from the first day after modeling, the control group mice were intraperitoneally injected with 0.1 ml of 0.9% sodium chloride solution, and the model group mice were intraperitoneally injected with 0.1 ml of 0.9% sodium chloride solution. The JWH133 intervention group mice were intraperitoneally injected with 0.1 ml of JWH133 (2.5 mg/kg, dissolved in physiological saline), and the JWH133+AM630 antagonistic group mice were intraperitoneally injected with 0.1 ml of JWH133 (2.5 mg/kg) and AM630 (2.5 mg/kg). After 28 days, all mice were killed; the lung tissue was obtained, pathological changes were observed, and alveolar inflammation scores and Ashcroft scores were calculated. The content of type Ⅰ collagen in the lung tissue of the four groups of mice was measured using immunohistochemistry. The levels of interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in the serum of the four groups of mice were measured using enzyme-linked immunosorbent assay (ELISA), and the content of hydroxyproline (HYP) in the lung tissue of the four groups of mice was measured. Western blotting was used to measure the protein expression levels of type Ⅲ collagen, α-smooth muscle actin (α-SMA), extracellular signal regulated kinase (ERK1/2), phosphorylated P-ERK1/2 (P-ERK1/2), and phosphorylated ribosome S6 kinase type 1 (P-p90RSK) in the lung tissue of mice in the four groups. Real-time quantitative polymerase chain reaction was used to measure the expression levels of collagen Ⅰ, collagen Ⅲ, and α-SMA mRNA in the lung tissue of the four groups of mice. Results: Compared with the control group, the pathological changes in the lung tissue of the model group mice worsened, with an increase in alveolar inflammation score (3.833±0.408 vs. 0.833±0.408, P<0.05), an increase in Ashcroft score (7.333±0.516 vs. 2.000±0.633, P<0.05), an increase in type Ⅰ collagen absorbance value (0.065±0.008 vs. 0.018±0.006, P<0.05), an increase in inflammatory cell infiltration, and an increase in hydroxyproline levels [(1.551±0.051) μg/mg vs. (0.974±0.060) μg/mg, P<0.05]. Compared with the model group, the JWH133 intervention group showed reduced pathological changes in lung tissue, decreased alveolar inflammation score (1.833±0.408, P<0.05), decreased Ashcroft score (4.167±0.753, P<0.05), decreased type Ⅰ collagen absorbance value (0.032±0.004, P<0.05), reduced inflammatory cell infiltration, and decreased hydroxyproline levels [(1.148±0.055) μg/mg, P<0.05]. Compared with the JWH133 intervention group, the JWH133+AM630 antagonistic group showed more severe pathological changes in the lung tissue of mice, increased alveolar inflammation score and Ashcroft score, increased type Ⅰ collagen absorbance value, increased inflammatory cell infiltration, and increased hydroxyproline levels. Compared with the control group, the expression of α-SMA, type Ⅲ collagen, P-ERK1/2, and P-p90RSK proteins in the lung tissue of the model group mice increased, while the expression of type Ⅰ collagen, type Ⅲ collagen, and α-SMA mRNA increased. Compared with the model group, the protein expression of α-SMA (relative expression 0.60±0.17 vs. 1.34±0.19, P<0.05), type Ⅲ collagen (relative expression 0.52±0.09 vs. 1.35±0.14, P<0.05), P-ERK1/2 (relative expression 0.32±0.11 vs. 1.14±0.14, P<0.05), and P-p90RSK (relative expression 0.43±0.14 vs. 1.15±0.07, P<0.05) decreased in the JWH133 intervention group. The type Ⅰ collagen mRNA (2.190±0.362 vs. 5.078±0.792, P<0.05), type Ⅲ collagen mRNA (1.750±0.290 vs. 4.935±0.456, P<0.05), and α-SMA mRNA (1.588±0.060 vs. 5.192±0.506, P<0.05) decreased. Compared with the JWH133 intervention group, the JWH133+AM630 antagonistic group increased the expression of α-SMA, type Ⅲ collagen, P-ERK1/2, and P-p90RSK protein in the lung tissue of mice, and increased the expression of type Ⅲ collagen and α-SMA mRNA. Conclusion: In mice with bleomycin-induced pulmonary fibrosis, the cannabinoid type-2 receptor agonist JWH133 inhibited inflammation and improved extracellular matrix deposition, which alleviated lung fibrosis. The underlying mechanism of action may be related to the activation of the ERK1/2-RSK1 signaling pathway.

A survey on the agricultural profession-related injuries among 11 902 rural residents in Shandong province / 中华流行病学杂志

Objective To understand the prevalence and risk factors of agricultural activities related injuries among rural residents in Shandong province. Methods A retrospective investigation was conducted among agricultural profession-related workers in 20 villages with multistage cluster sampling method in Shandong province. Four times face-to-face interview were conducted by trained interviewers, including 32 students and local medical personnel under constructed questionnaires.Accidental injuries occurred in the activities or in the agricultural profession-related jobs were recorded, from May 1st 2009 to April 30st 2010. Data was input and analyzed by SPSS 13.0 statistical software. Results A total of 837 cases reported at least 1 job-related injury out of the 11 902 people who had been surveyed in one year. The crude incidence rate was 7.03% and the standardized incidence rate was 7.36%, higher in males (9.01%) than in females (4.10%), X2= 105.53, P=0.000.Children and adolescents (≤ 14 aged) had the higher incidence rate (9.50%), X2=9.70, P=0.008.People working in the area of commercial service related to agricultural products had the highest incidence rate (12.94%). In particular, those occupations that related to agricultural construction or materials appeared to have had higher incidence rates as 16.80% and 15.59% respectively, than other kinds of jobs (X2= 167.30, P=0.000). There were higher proportion of injuries occurred in the roads (28.79%), in the fields(28.08%) during labor work(38.00%) transportation(27.97%), respectively.The seasonality of agricultural injures mostly occurred between June and August, accounted for 47.43%. Major external causes related to injuries were instruments or tools (31.42%) being used,transportation (24.13%) and falls (20.19%). Wounds on limbs took the majority (56.39%). The accidental self-inflicted injury occupied 76.82%, while accidents to passive injuries occupied 11.47%,other kinds accounted for 11.71%. Most of the accidents caused mild or moderate damage, accounted for 60.22% and 30.34% respectively. 7 cases died of injuries, with the fatality rate as 0.84% and the mortality rate was 58.81 per one hundred thousand. 72 cases ended up in disability caused by injuries,with the morbidity rate as 6.05 per thousand. Answers to the major internal causes of injuries appeared to be: "did not know how to protect oneself" (29.87%) with females (45.41%) in particular,followed by "over fatigue" and "inappropriate treatment" which took the 2nd place in males. Major natural environmental factors of injuries would relate to "high air temperature and humidity but lower wind velocity"(14.93%), "unclear signs on the country road"(12.19%), "the sky was cloudy or dark"(10.87%), "slippery road caused by rain or snow" (10.51%), "kids were unintended" (10.27%) etc.Most of the wounded received treatment clinically (50.18%), with the percentile (P50) of medical cost as 182.76 RMB (Yuan). The proportion of inpatient was 27.72% and with percentile of time as P50=7.57 day and cost as P50=2840.00 RMB Yuan. The wounded had a rest of P50=5.9 days, with an indirect cost as P50=233.16 RMB Yuan. Conclusion The results of this study indicated that the incidence of agricultural profession-related injuries was high, with serious harm. Behavioral intervention and awareness of injuries should be enhanced, together with the improvement of environmental condition.

Repeated gonadotropin stimulations lower the developmental potential of mouse oocytes / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the effect of repeated gonadotropic stimulations on the developmental potential and growth differentiation factor-9 (GDF-9) expression of mouse oocytes.</p><p><b>METHODS</b>Female Kunming mice were treated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (HCG) for 3 times, and the control mice were treated with normal saline. The two groups of mice were both stimulated subsequently to obtain the mature oocytes. Immunocytochemical staining was employed to evaluate GDF-9 expression in the oocytes. The oocytes were then inseminated and cultured till the formation of blastocysts to compare the cleavage rate and blastocyst formation rate between the groups.</p><p><b>RESULTS</b>A total of 253 mature oocytes were obtained in the repeated stimulation group, with a mean of 11.5 oocytes from each mouse; 521 mature oocytes were obtained in the control group with a significantly greater mean number of 32.6 from each mouse (P<0.05). The average optical density and integrated optical density for GDF-9 expression were significantly lower in the oocytes in repeated stimulation group than in the control group (P<0.05 and 0.01, respectively). After insemination, the cleavage rate were comparable between repeated stimulation group and the control group (85.6% vs 88.8%), but the blastocyst formation rate was significantly lower in repeated stimulation group (20.8% vs 35.2%, P<0.01).</p><p><b>CONCLUSION</b>Repeated gonadal stimulation decreases the developmental potential of mouse oocytes possibly due to reduced GDF-9 expression.</p>