α-Crystallin B (cryAB) is the most abundant small heat shock protein in cardiomyocytes (CMs) and has been shown to have potent antiapoptotic properties. Because the mechanism by which cryAB prevents apoptosis has not been fully characterized, we examined its protective effects at the cellular level by silencing cryAB in mouse neonatal CMs using lentivector-mediated transduction of short hairpin RNAs. Subcellular fractionation of whole hearts showed that cryAB is cytosolic under control conditions, and after H(2)O(2) exposure, it translocates to the mitochondria. Phosphorylated cryAB (PcryAB) is mainly associated with the mitochondria, and any residual cytosolic PcryAB translocates to the mitochondria after H(2)O(2) exposure. H(2)O(2) exposure caused increases in cryAB and PcryAB levels, and cryAB silencing resulted in increased levels of apoptosis after exposure to H(2)O(2). Coimmunoprecipitation assays revealed an apparent interaction of both cryAB and PcryAB with mitochondrial voltage-dependent anion channels (VDAC), translocase of outer mitochondrial membranes 20 kDa (TOM 20), caspase 3, and caspase 12 in mouse cardiac tissue. Our results are consistent with the conclusion that the cardioprotective effects of cryAB are mediated by its translocation from the cytosol to the mitochondria under conditions of oxidative stress and that cryAB interactions with VDAC, TOM 20, caspase 3, and caspase 12 may be part of its protective mechanism.

Calnexin (CNX) is an endoplasmic reticulum (ER) quality control chaperone that has been implicated in ER stress. ER stress is a prominent pathological feature of various pathologic conditions, including cardiovascular diseases. However, the role of CNX and ER stress has not been studied in the heart. In the present study, we aimed to characterize the role of CNX in cardiomyocyte physiology with respect to ER stress, apoptosis, and cardiomyocyte Ca(2+) cycling. We demonstrated significantly decreased CNX mRNA and protein levels by LentiVector mediated transduction of targeting shRNAs. CNX silenced cardiomyocytes exhibited ER stress as evidenced by increased GRP78 and ATF6 protein levels, increased levels of spliced XBP1 mRNA, ASK-1, ERO1a, and CHOP mRNA levels. CNX silencing also led to significant activation of caspases-3 and -9. This activation of caspases was associated with hallmark morphological features of apoptosis including loss of sarcomeric organization and nuclear integrity. Ca(2+) imaging in live cells showed that CNX silencing resulted in Ca(2+) transients with significantly larger amplitudes but decreased frequency and Ca(2+) uptake rates in the basal state. Interestingly, 5 mM caffeine stimulated Ca(2+) transients were similar between control and CNX silenced cardiomyocytes. Finally, we demonstrated that CNX silencing induced the expression of the L-type voltage dependent calcium channel (CAV1.2) but reduced the expression of the sarcoplasmic reticulum ATPase (SERCA2a). In conclusion, this is the first study to demonstrate CNX has a specific role in cardiomyocyte viability and Ca(2+) cycling through its effects on ER stress, apoptosis and Ca(2+) channel expression.

BACKGROUND: Pouchitis is the most common inflammatory complication in ulcerative colitis patients undergoing postoperative construction of an IPAA. Pouchitis refers to a spectrum of diseases, and as such, it lacks a universally accepted definition as well as validated instruments to measure disease activity and treatment response. Assessing pouchitis activity is challenging, and methods for diagnosis and classification of severity of pouchitis are not universally agreed upon. CLINICAL FEATURES:Pouchitis is characterized by a constellation of clinical symptoms, including increased stool frequency, urgency, incontinence, bleeding, and rarely constitutional symptoms such as malaise and lowgrade fever. However, these symptoms are subjective, and similar symptoms can be caused by noninflammatory conditions including anal sphincter dysfunction, anastomotic strictures, occult leaks, pouch inlet obstruction, and cuffitis. Objective scores that include endoscopic and histologic criteria have been developed for subjects with an IPAA. However, these instruments are not validated for measuring pouchitis disease activity and are associated with a number of challenges. In addition, the clinical components of the scores correlate poorly with endoscopic and histologic findings. CONCLUSION AND FUTURE DIRECTIONS:There is a need for prospective studies to facilitate the development and validation of novel instruments that are valid, reliable, and responsive to change that would facilitate the development of therapeutic agents for the treatment of pouchitis.

Body: Background: FMT is a highly-effective therapy for recurrent Clostridium difficile infections. To develop an effective FMT program, stool donors are required and essential for FMT; however, they are difficult to recruit and retain. We aimed to identify factors which could optimize donor program and imrpove donor retention. Methods: A 32-item questionnaire was disseminated via several social media platforms as well university electronic mailing lists in Edmonton and Kingston, Canada; London and Nottingham, England; Indianapolis, and Boston, USA. Items included questions regarding motivation for becoming a stool donor, knowledge and perception of FMT, and history of being a blood donor or considered being an organ donor. Questions regarding economic compensation, screening process, and time commitment were also posted. Four logistic regression models incorporating these variables were built to predict willingness to donate stool. Results: A total of 802 respondents (387 [48.3%] from 21-30 years old; 573 [71.4%] women; 323 [40%] healthcare professionals) completed the questionnaire between June 22 and September 28, 2017 (table 1). 334 (41.7%) participants indicated altruism as the main reason for being a stool donor, while 282 (35.2%) indicated economic compensation was an additional motivator. Younger participants, students, and US residents were more likely to be motivated by economic compensation than those older, non-students and living in the UK and Canadian residents. Those who had a positive attitude towards FMT were more willing to receive and donate for FMT. Those more willing to donate for FMT were more knowledgeable about FMT, and did not find donating or the screening process invasive or time consuming. However, the willingness to donate decreased with required frequency of donation. Although economic compensation appeared to motivate donors, knowing how FMT helps individuals was more influential. One recurrent theme impeding stool donation was the logistics of collecting and transporting feces. Based upon the logistic regression model the impact of each variable (odds ratio; 95% confidence interval) on willingness to donate was shown in table 2. The model (#4) which incorporated all these variables predicted the willingness to donate stool with the highest accuracy (ROC= 0.86). Conclusion: Although a significant proportion of participants identified altruism as the main reason for becoming a stool donor, economic compensation, and positive feedback from their stool donation are additional motivators. The screening process, high frequency of stool donation, and logistics of collecting/ transporting stools were potential deterrents. These variables should be taken into consideration recruiting and retaining stool donors.