Combining digital pill and smartphone data to quantify medication adherence in an observational psychiatric pilot study

Digital medicine systems (DMSs) offer a potential solution to increase medication adherence, which is an important barrier to treatment of psychiatric disorders. In this pilot, we enrolled N = 24 individuals diagnosed with severe mental illness to use an FDA-approved DMS for 5 months. We also collected digital phenotyping smartphone data to study behavioral associations with medication adherence. Our results suggest it is feasible to use the system, and we identified longitudinal associations between adherence and some of the communication-based phenotyping features. Larger studies and a focus on data quality are important next steps for this work.

Sociodemographic characteristics of missing data in digital phenotyping

The ubiquity of smartphones, with their increasingly sophisticated array of sensors, presents an unprecedented opportunity for researchers to collect longitudinal, diverse, temporally-dense data about human behavior while minimizing participant burden. Researchers increasingly make use of smartphones for "digital phenotyping," the collection and analysis of raw phone sensor and log data to study the lived experiences of subjects in their natural environments using their own devices. While digital phenotyping has shown promise in fields such as psychiatry and neuroscience, there are fundamental gaps in our knowledge about data collection and non-collection (i.e., missing data) in smartphone-based digital phenotyping. In this meta-study using individual-level data from six different studies, we examined accelerometer and GPS sensor data of 211 participants, amounting to 29,500 person-days of observation, using Bayesian hierarchical negative binomial regression with study- and user-level random intercepts. Sensitivity analyses including alternative model specification and stratified models were conducted. We found that iOS users had lower GPS non-collection than Android users. For GPS data, rates of non-collection did not differ by race/ethnicity, education, age, or gender. For accelerometer data, Black participants had higher rates of non-collection, but rates did not differ by sex, education, or age. For both sensors, non-collection increased by 0.5% to 0.9% per week. These results demonstrate the feasibility of using smartphone-based digital phenotyping across diverse populations, for extended periods of time, and within diverse cohorts. As smartphones become increasingly embedded in everyday life, the insights of this study will help guide the design, planning, and analysis of digital phenotyping studies.

Inhibition of mouse melanoma cell proliferation by corticotropin-releasing hormone and its analogs

BACKGROUND

Observations that epidermal cells release both corticotropin-releasing hormone (CRH) and proopiome lanocortin (POMC) peptides has raised questions about the physiological relevance of this hypothalamo-pituitary-like system in mammalian skin. As CRH has shown anti-proliferative effects on cultured keratinocytes, we tested whether CRH can also regulate growth of melanoma cells.

MATERIALS AND METHODS

CRH, [D-Glu20]-CRH, [D-Pro5]-CRH, acetyl-cyclo(30-33)[D-Phe12,D-Glu20,Nle21,D-His32,Lys33,D-Nle38]-CRH(4-41), acetyl-cyclo(30-33)[D-Phe12,Nle18,D-Glu20,Nle21,D-Ala32]-urotensin I(4-41), urocortin, and sauvagine were tested on Cloudman melanoma cell proliferation in culture and B16 melanoma tumor growth in C57B1/6 mice. Calcium-sensitive fluorescence measurements were used to examine the effect of CRH on intracellular Ca2+ signaling. The effects of CRH and [D-Glu20]-CRH on blood pressure were compared by measuring mean arterial pressure in anesthetized rats.

RESULTS

CRH and six analogs were tested, and all demonstrated exceptional potency in inhibiting Cloudman cell proliferation in culture, with half-maximal effective concentrations ranging between 0.2 and 100 pM. The amplitude of ionomycin-induced Ca2+ influx into Cloudman cells grown in suspension was reduced by 50% after 48-hr exposure to CRH. Daily injections of CRH or [D-Glu20]-CRH, 100 micrograms/kg.day s.c., for 5 days, reduced net B16 tumor volume in mice by 30-60% compared to control animals. [D-Glu20]-CRH was less hypotensive compared to CRH, despite having similar anti-proliferative potency.

CONCLUSION

CRH, and various analogs thereof, inhibit proliferation of Cloudman cells in culture, and inhibit B16 tumor growth rate in vivo, most likely by activation of endogenous CRH1 receptors and subsequent altered intracellular Ca2+ signaling. CRH analogs, such as [D-Glu20]-CRH, with less hypotensive activity may provide new directions of therapy for melanoma.

Nuclear Ca2+/calmodulin translocation activated by mu-opioid (OP3) receptor

Previous evidence has suggested a role for calmodulin (CaM) in opioid receptor signaling. We demonstrate here that morphine stimulation of the mu-opioid (OP3) receptor causes rapid CaM translocation to the nucleus in OP3-transfected human embryonic kidney (HEK)-293 cells and in SH-SY5Y human neuroblastoma cells. Ca2+ influx into the cells resulting from OP3 receptor activation was required for nuclear CaM translocation. Moreover, in HEK-OP3 and SH-SY5Y cells, increased nuclear CaM content was associated with enhanced phosphorylation of the nuclear transcription factor cyclic AMP-responsive element-binding protein. This appeared to be mediated by Ca2+/CaM kinases and also by a pathway involving protein kinase C. CaM was previously shown to bind directly to the OP3 receptor and to be released from the plasma membrane on agonist stimulation. To test whether OP3-mediated CaM release contributes to nuclear CaM signaling, we used a mutant OP3 receptor (K273A) with reduced affinity for CaM that fails to release CaM from the plasma membrane. K273A-OP3 activated Ca2+ influx to a similar extent as wild-type OP3; however, CaM translocation to the nucleus was attenuated. These results indicate that OP3-stimulated Ca2+ influx results in nuclear CaM translocation, which appears to be enhanced by simultaneous CaM release by OP3 wild-type receptor from plasma membranes. These results suggest a novel Ca2+/CaM signaling pathway of opioid receptors in the regulation of transcriptional activity.