Pre-conditioning with synthetic CpG-oligonucleotides attenuates myocardial ischemia/reperfusion injury via IL-10 up-regulation

The aim of the study was to investigate whether pre-conditioning with CpG-oligodeoxynucleotides (CpG-ODN) may change cardiac ischemia/reperfusion (I/R)-dependent inflammation and modulates infarct size and cardiac performance. WT and TLR9-deficient mice were pre-treated with 1668-, 1612- and H154-thioate or D-Gal as control. Priming with 1668-thioate significantly induced inflammatory mediators in the serum and a concomitant increase of immune cells in the blood and spleen of WT mice. Furthermore, it induced myocardial pattern recognition receptors and pro-inflammatory cytokines peaking 2 h after priming and a continuous increase of IL-10. 16 h after pre-conditioning, myocardial ischemia was induced for 1 h. Infarct size determined after 24 h of I/R was reduced by 75 % due to pre-conditioning with 1668-thioate but not in the other groups. During reperfusion, cytokine expression in 1668-thioate primed mice increased further with IL-10 exceeding the other mediators by far. These changes were observed neither in animals pre-treated with 1612- or H154-thioate nor in TLR9-deficient mice. The 1668-thioate-dependent increase of IL-10 was further supported by results of a micro-array analysis 3 h after begin of reperfusion. Block of IL-10 signaling increased I/R size and prevented influence of priming. In the group pre-treated with 1668-thioate, cardiac function was preserved 24 h, 14 days and 28 days after I/R, whereas animals without pre-conditioning exhibited impaired heart function 24 h and 14 days after I/R. The excessive 1668-thioate-dependent IL-10 up-regulation during pre-conditioning and after I/R seems to be the key factor for reducing infarct size and improving cardiac function. This is in agreement with the finding that IL-10 block prevents cardioprotection by pre-conditioning.

Advance directives and withdrawal of dialysis in the United States, Germany, and Japan

OBJECTIVE

To determine the role of advance directives in decisions to withdraw chronic dialysis in the United States, Germany, and Japan.

DESIGN

Survey by questionnaire.

PARTICIPANTS

Seventy-two American, 87 German, and 73 Japanese nephrologists.

MAIN OUTCOME MEASURES

Each nephrologist's total number of (1) dialysis patients, (2) cases of withdrawal of dialysis, (3) patients with advance directives, and (4) uses of such directives. Nephrologists also stated whether they would continue or stop dialysis in 8 hypothetical cases.

RESULTS

American, German, and Japanese nephrologists reported withdrawing dialysis for 5.1%, 1.6%, and 0.7% of their patients in the last year, respectively. Thirty percent of American patients had advance directives, and such directives were used in decision making for 3.2% of all patients. Only 0.3% of German and Japanese patients had advance directives, and such directives were used in decision making for 0.09% of patients. When asked about a hypothetical mentally incompetent patient whose family requests withdrawal of dialysis, American nephrologists were much more likely to stop dialysis in the absence of an advance directive than German or Japanese nephrologists. However, almost all nephrologists from the 3 countries would stop dialysis when a family request to withdraw was supported by a patient advance directive.

CONCLUSIONS

There is a high prevalence of advance directives among American dialysis patients, and such directives frequently play a role in decision making. German and Japanese nephrologists appear willing to follow advance directives, but the low prevalence of such directives limits the frequency of their use.