Objective: To investigate the effect of cobalt chloride (CoCl2) on transgene expression and viral particle titers in tumor cells infected by conditionally replicating adenovirus expression vector with hypoxia response elements(HRE)-regulated E1AE1B expression (Ad-5HRE-E1AE1B-RFP) and non-HRE regulated replication-deficient adenovirus expression vector (Ad-EGFP, Ad-Luc) in vitro and in vivo. Methods: Ad-5HRE-E1AE1B-RFP had five duplicated HRE and mini CMV acted as a promoter to drive E1AE1B expression and constitutive expression of RFP as reporter. The hypoxia model was optimized by exposing tumor cells to different concentrations of CoCl2. The hypoxia-inducible factor 1 alpha (HIF-1α) protein expression was determined by Western blotting. Under the optimized hypoxia model, the positive expression of exogenous gene and virus replication of Ad-5HRE-E1AE1B-RFP or Ad-EGFP-infected tumor cells were examined by conversed microscopic observation, FACS analysis and plaques formation test. Furthermore, transgene expression induced by combined application of hypoxia-inducible replicative adenovirus and replication deficient adenovirus (Ad-Luc) was also evaluated by examining the lucifererse activity in xenografted tumor models in nude mice by micro PET. Results: Western blotting results showed that CoCl2 at 0.4 and 0.08 μg/mL could stabilize and acumulate HIF-1α protein in gastric cancer SGC7901 cells, which could better mimic hypoxia condition. The microscopic observation and FACS analysis showed that CoCl2 at 0.4 μg/mL could remarkably increase the transduction efficacy of Ad-5HRE-E1AE1B-RFP, which was verified by significant increase in the percentage of positive expression of exogenous gene RFP and fluorescence intensity. But plaques formation test showed that Ad-5HRE-E1AE1B-RFP had no replication. CoCl2 0.4 μg/mL augmented the tranduction efficacy and expression levels of non-HRE regulated replication deficient adenovirus Ad-EGFP and Ad-Luc. Combined intratumoral injection of Ad-5HRE-E1AE1B-RFP and Ad-Luc significantly increased the expression of Ad-Luc in nude mice.Conclusion: CoCl2 markedly enhances transgene expression of recombinant adenovirus. However, the underlying mechanism is not only related to the CoCl2-induced hypoxia, but also probably related to regulation of gene transcription.

The theoretical basis of premature aging originates from The Yellow Emperor's Inner Classic. The etiology of premature aging is complex， and the disease mechanism is based on deficiency. The treatment for premature aging is based on tonicity. The essence-Qi-spirit theory of Qiluo doctrine summarizes that "essence is the origin of life， Qi is the driving force of life， and spirit is the embodiment of life"， which is the law of life. The theory puts forward the core disease mechanism of aging， which states that "deficiency of kidney essence is the root of aging， deficiency of primordial Qi is the key to aging， impairment of soma and spirit is the manifestation of aging". The theory also proposes the treatment of "tonifying kidney and supplementing essence， harmonizing Yin and Yang， warming and supporting primordial Qi， and nourishing soma and spirit" and the representative anti-aging drugs. The article unfolds from the perspective of the concepts of natural life span， premature senility before fifty， decline， and aging and also explains the origins and connotations of premature aging. The article explains the disease mechanism of premature aging under the guidance of the essence-Qi-spirit theory of Qiluo doctrine， which is "early deprivation of kidney essence， deficiency of primordial Qi， accumulation of deficiencies into impairment， and decline and impairment of soma and spirit"， summarizes the progress of modern medical research on the treatment of premature aging and representative drugs， and finds that Bazi Bushen capsules have a precise therapeutic effect on the overall premature aging， systematic functional decline， and related diseases. The study provides theoretical basis and new ideas to solve the problems of premature aging and geriatric diseases.