Cheng Jingqiu

Lovastatin inhibits adipogenesis and prevents osteonecrosis in steroid-treated rabbits

OBJECTIVES To investigate in vivo effects of lovastatin on inhibition of adipogenesis, an important mechanism of steroid-induced osteonecrosis, and on prevention of occurrence of steroid-induced osteonecrosis in rabbits. METHODS Fifty-four rabbits were intramuscularly injected once with 20mg/kg of methylprednisolone acetate (MPSL). Then, they were divided into two groups: lovastatin was given in Group I and placebo was given in Group II. And another 16 rabbits were injected with physiologic saline (PS) as a control (Group III). Hematological examination was performed for serum lipid levels. Both the femora and the humeri were histopathologically examined for the presence of osteonecrosis before the injection and 1, 2, 4 and 12 weeks after the injection. RESULTS The serum lipid levels were significantly higher in Group II than in Groups I and III 1, 2 and 4 weeks after the injection. The incidence of osteonecrosis was significantly higher in Group II (69%) than in Group I (36%) and Group III (0%). Pathological examination showed less serious adipogenesis and bone death in Group I than in Group II. The size and area of the fat cells in the bone marrow were significantly smaller in Group I (47.5+/-1.3 microm, 25%) and Group III (41.7+/-1.6 microm, 12%) than in Group II (59.8+/-6.3 microm, 51%) (P< 0.001). CONCLUSION Lovastatin can prevent development of steroid-induced osteonecrosis in rabbits by inhibiting adipogenesis. Future evaluation on the effectiveness of lovastatin in the clinical practice is still necessary.

Circulating miRNAs might be promising biomarkers to reflect the dynamic pathological changes in smoking-related interstitial fibrosis

Cigarette smoking is the major risk factor for smoking-related interstitial fibrosis (SRIF). Despite recent advances, the molecular mechanisms involved in the initiation and progression of this disease remain elusive. We found 6 months of chronic mainstream smoking exposure induced SRIF in C57 mice, which was associated with pronounced enhanced oxidative stress, bronchoalveolar inflammation and fibrosis but not apoptosis of alveolar septal cell. We used Affymetrix microRNA (miRNA) arrays to determine the temporal alteration in global gene expression of peripheral blood during the progression of diffuse pulmonary interstitial fibrosis in C57 mice. Microarray analysis revealed the upregulation of 3 miRNAs (miR-92b, miR-700 and miR-668) and the downregulation of 5 miRNAs (let-7e, miR-142-5p, miR-350, miR-19a and miR191*) in the peripheral blood of mice exposed to mainstream smoking for 1, 2, 3 and 6 months. We proposed that circulating miRNAs might be promising biomarkers to reflect the dynamic pathological changes of SRIF related interstitial fibrosis.

Variation of host cell tropism of porcine endogenous retroviruses expressed in chinese Banna minipig inbred.

A serious donor-organ shortage urges the use of animal donors to treat a wide appropriate variety of major health problems including organ failure and diabetes. However, the promise of clinical xenotransplantation is offset at the present time by the potential of a public health risk due to the cross-species transmission of pathogens from animal donors to human patients. In particular, the transmission of porcine endogenous retrovirus (PERV) is a major concern. In this study, cell tropism of PERV was tested by in vitro infection of human primary cells and cell lines. Coculture of PERV supernatant derived from PK15 with human primary cells and cell lines resulted in the transfer and expression of PERV-specific sequences and the establishment of a productive infection. In the detection of tropism variation of PERV in pigs, 293 cells were cocultured with mitogenic-activated and lethally irradiated PBMC from 12 Banna minipig inbred (BMI). The results were that six coculture groups were PERV-positive. However, infectious virus was not detected when activated PBMC from the other 7 pigs were cocultivated with human cells known to be permissive for PERV, which indicated a tropism variation among the tested individuals. All these findings demonstrate that the presence of endogenous viruses in source animals needs to be carefully considered when the infectious disease potential of xenotransplantation is being assessed.

Circulating biomarkers of hazard effects from cigarette smoking.

Smoking, leading to over 438,000 annual deaths in the US and 92 billion US dollars in lost productivity, is an important risk factor for several diseases. Global smoking statistics for 2002 have shown that 80,000 to 100,000 children worldwide start smoking every day. Human biomonitoring nowadays has provided an efficient and cost-effective means of measuring human exposures and biological effects of smoking. To review the utility of biomarkers in reflecting the hazard from cigarette smoking, we comprehensively searched the Cochrane Library, Medline and EMbase from 1966 to May 2010 with the language limit of English. We found that the currently used biomarkers, such as tobacco-specific metabolites, smoking-induced genotoxic products, may not scientifically reflect the hazard from cigarette smoking. More research is needed to find out more effective biomarkers for estimating hazards from cigarette smoking. This paper is expected to help researchers understand the current utilization of biomarkers related to cigarette smoking and to provide suggestive guides to tobacco companies in producing less-toxic cigarettes, thus to provide a safe way to smoke.Smoking, leading to over 438,000 annual deaths in the US and 92 billion US dollars in lost productivity, is an important risk factor for several diseases. Global smoking statistics for 2002 have shown that 80,000 to 100,000 children worldwide start smoking every day. Human biomonitoring nowadays has provided an efficient and cost-effective means of measuring human exposures and biological effects of smoking. To review the utility of biomarkers in reflecting the hazard from cigarette smoking, we comprehensively searched the Cochrane Library, Medline and EMbase from 1966 to May 2010 with the language limit of English. We found that the currently used biomarkers, such as tobacco-specific metabolites, smoking-induced genotoxic products, may not scientifically reflect the hazard from cigarette smoking. More research is needed to find out more effective biomarkers for estimating hazards from cigarette smoking. This paper is expected to help researchers understand the current utilization of biomarkers related to cigarette smoking and to provide suggestive guides to tobacco companies in producing less-toxic cigarettes, thus to provide a safe way to smoke.