Melatonin Activation of PKC in Human Myometrial Cells. Casey Cable Grand Rounds 4 September 2008 Research Advisor: Dr.

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1 Melatonin Activation of PKC in Human Myometrial Cells Casey Cable Grand Rounds 4 September 2008 Research Advisor: Dr. James Olcese

2 Melatonin 5-hydroxy-N-acetyl-tryptamine primary hormone product of the pineal gland secreted solely at night, the hormonal messenger of night

3 Research Tools Cultured htert immortalized human myometrial cells (Condon et al, 2002) Chemical treatments Iodo-Melatonin (I-Mel) more stable form of melatonin analogue 4P-PDOT specific Mel 2 receptor antagonist at used concentrations PDBU PKC activator C1 general inhibitor of PKC Phospho-PKC antibodies of various isoforms

4 Melatonin and Parturition Spontaneous term human births occur predominantly in late night/early morning

5 Melatonin effects on myometrial smooth muscle cell contractions in vitro involving PKC signaling. 100 control % of untreated controls treated 0 I-MEL -MEL + 4PPDOTI-MEL + C1 4PPDOT C1 Treatments Sharkey et al, Submitted

6 Model for melatonin s synergistic actions on myometrial contractions

7 Identification of PKC isoform (α/β, δ, μ, θ, ζ/λ) P-PKCpan P-PKCα/β 80kD 80kD Control I- MEL PDBU Control I- MEL I-MEL + P-PDOT Melatonin activation of P-PKCα/β

8 Immunoprecipitation IP using PKCα antibody (+/- phospho) attached to beads Western blot using phosph-pkcα/β antibody Immno-depleted sample (-PKA α) IP PKCα sample 80kD Control I- MEL I-MEL + P-PDOT Control I- MEL I-MEL + P-PDOT Melatonin activation of P-PKCα

9 PKC Assay Measures the activity of PKC Immunoprecipitation with PKCα antibody

10 Summary Previously shown that melatonin augments oxytocin induced contractility in htert myometrial cells Synergy has been blocked by C1 (general PKC inhibitor) PKCα is activated by melatonin Consistent with reports that the α isoform is activated by oxytocin. (Hurt et al, 2000) Employing melatonin for the induction of labor or key for other drug targets

11 Questions? Special thanks to Jim Sharkey, Holly Sikes, Anne Maxwell and Dr. Olcese.

12 Histone Deacetylase Inhibitors: A TBI Pilot Study Jeff Cummings Ethan Cohen

13 Histone Deacetylase (HDAC) Family of proteins involved in the regulation of gene expression. Divided into three classes based on sequence homology Class II HDACs are most intensely studied in the context of cell signaling In neurons, class II HDACs can translocate from cytoplasm to nucleus Trafficking ability is associated with cell death mechanisms

14 Immunostaining for HDAC4

15 Hippocampus

16 HDAC Inhibitors Inhibitors of HDAC activity have shown positive results in reducing cell death HDAC inhibition prevents transcriptional repression, allowing for survival genes to be expressed Mechanism in brain is poorly understood

17 HDAC Inhibitors Clinical Relevance Inhibition of HDACs have shown strong promise in models of neurodegenerative conditions such as Huntington s, ALS, Parkinson s, ischemia, and possibly Alzheimer s by decreasing neuronal death promoting cell survival

18 TBI Background Estimated 1.4 million US persons have traumatic brain injury each year of whom 80 90,000 have long term disability Incidence estimates based on 74,517 persons hospitalized for traumatic brain injury related diagnoses in 2002 in 12 states conducting surveillance Overall incidence of hospitalization 79 per 100,000 population

19 Experiment Rationale We want to test the hypothesis that HDAC inhibition may reduce lesion cavity size and may effect the location of HDACs in the damaged region

20 TBI Model 10 Rats 7wk old Male Sprague Dawley 4 Treatments 3 Vehicles 3 Shams Procedure Isoflurane anesthetic Incision over bregma Craniotomy anterior to bregma, midline Controlled Cortical Impact

21 Treatment Protocol Treatment Sodium Butyrate (NaBu) 1g/kg body weight at 1 hr post TBI *.5g/kg at 3 and 6 hr post TBI * 1g/kg every 24 hr post TBI for 5 days * Vehicle PBS * Same time protocol as NaBu regiment Sham No treatment * Volume of.5 ml given Intraperitoneal

22 Behavior Study Morris Water Maze 3 tests: Hidden Platform 8 day study, 4 trials/day 90 second search criterion Platform Removal Day 9, 30sec probe trial Time spent in quadrant/total time Cued Trial Learning Day 9 and 10, 4 trials/day 90 second search criterion

23 Morris Water Maze

24 Morris Water Maze

25 Morris Water Maze

26 Body Weight Grams Sham Vehicle NaBu Days

27 Morris Water Maze Latency (s) Sham Vehicle NaBu Days

28 MWM By Trial Latency (s) Trial Sham Vehicle NaBu

29 Reference Memory Trial Quadrant/Total Time (s) Sham Vehicle NaBu

30 Cued Learning Test Latency (s) Sham Vehicle NaBu Day

31 Cued Learning Test Latency (s) Trial Sham Vehicle NaBu

32 Limitations Water Maze Tub to Platform Ratio Video Monitoring Sample Size

33 Further Studies Lesion Cavity Size Immunohistochemistry: Glial staining HDAC 4

34 Acknowledgements Dr. Ouimet Mike Darcy Dr. Vanlandingham FSU college of Medicine Ken Winnard Emily Langerhan

35 The Relation Between Caregivers Depressive Symptoms and Adherence to Blood Glucose Monitoring Zarna Dahya, B.S. Kimberly A. Driscoll, Ph.D. Suzanne Bennett Johnson, Ph.D. Larry C. Deeb, M.D. Janet H. Silverstein, M.D. This study was funded by the National Institute of Heart, Lung, and Blood (NHLBI); R01 HL69736, PI: Suzanne Bennett Johnson, Ph.D.

36 What is Type 1 Diabetes? Autoimmune disease in which the insulin producing B cells are attacked by one s own body Disease management is complex and time consuming Daily blood glucose monitoring Insulin injections Diet Exercise

37 Type 1 Diabetes Statistics 186,300 (0.22%) people < 20 years of age 1 in every children & adolescents Accounts for 5-10% of cases of diabetes Peak incidence occurs during puberty ~ 10 to 12 years of age in girls ~ 12 to 14 years of age in boys American Diabetes Association & NIDDK, 2008

38 Diabetes Severity A1C Conducted every 3 months Gold standard Reflects average blood glucose for last 2-3 months Measures concentration of hemoglobin molecules in red blood cells that have glucose attached to them

39 Adherence Adherence to disease treatment regimens is 50% (Rapoff, 1999) Rates for diabetes blood glucose testing range from 69-71% (Delamater et al., 1988; Johnson et al., 1992) Non-adherence to the treatment regimen Weight loss Delays in pubertal and skeletal development Hypertension Nephropathy Glycosuria Diabetic ketoacidosis Hypoglycemia Diabetes Control and Complications Trial Research Group (DCCT), 1993

40 Caregiver Responsibilities Blood glucose monitoring 4 X/day Insulin by injections or intravenous pump Making sure the child receives adequate physical exercise Making sure the child follows a dietary regimen Time consuming and complex

41 Link Between Depressive Symptoms and Adherence Caregivers of children with chronic illnesses are at increased risk for developing depressive symptoms Depression in mothers of children with asthma has been linked to decreased adherence and poor medical outcomes (Bartlett, Krishnan, Reikert, Butz, Malveaux, Rand, 2004) 17-22% of mothers of children with type 1 diabetes experienced moderate to severe symptoms of depression (Horsch, McManus, Kennedy, & Edge, 2007; Jaser et al., 2007)

42 Research Questions: Adherence What are the adherence rates of blood glucose monitoring in children with type 1 diabetes? What is the relation between blood glucose testing adherence and A1C?

43 Research Questions: Caregiver Depressive Symptoms What percentage of caregivers with children with type 1 diabetes exhibit depressive symptoms? Are depressive symptoms related to blood glucose testing adherence? Are there differences in adherence rates to blood glucose monitoring in caregivers who exhibit depressive symptoms and those who do not?

44 Handling Diabetes Randomized clinical trial funded by NHLBI PI: Suzanne Bennett Johnson, Ph.D. Immediate (18 mo.) v. Delayed Treatment (24 mo.) Assess adherence intervention incorporated into routine clinical care of patients w/ type 1 diabetes Written prescribed treatment form Knowledge and skills Problem-solving skills This study = Visit 1 & Visit 2 3 months apart

45 Procedure Patients approached for participation by their endocrinologist Caregiver informed consent and child assent obtained Primary caregiver = person who brought child to the appointment was considered the primary caregiver Subset of the data were used including Questionnaires Blood glucose meter readings A1C results Data collection occurred every 3 months which coincided with routine clinic visits

46 Participants 108 patients with type 1 diabetes and their caregivers Recruited from 2 sites University of Florida Florida State University Inclusion criteria Diagnosis of type 1 diabetes Ages = 2-12 years Willingness to provide informed caregiver consent and child assent

47 Participant Characteristics Caregivers Age Sex Female 83.3% Male 16.7% Education < High school 30.6% > High school 69.4% Patients Age Disease Duration Sex Female Male 53.7% 46.3% Work Outside Home Yes No 75.7% 24.3% Married Yes No 73.1% 26.9%

48 Measures Center for Epidemiological Studies Depression Scale (CES-D; Radloff, 1977) 20-item measure used to assess depressive symptoms e.g., I felt sad, I thought my life had been a failure Internal consistency; α = 0.88 Blood glucose meter data Date and time of test Blood glucose test result A1C Indicator of the average glucose level over the past 2-3 months

49 Timeline Background Information Visit 1 Visit 2 X CES-D X A1C X X Meter data X

50 Results: Blood Glucose Testing Visit Mean (SD) Range %

51 Results: Blood Glucose Visit Mean (SD) Range Control- A1C %

52 Results: Depressive Symptoms in Caregivers %

53 Results: Depressive Symptoms & Adherence

54 Correlations A1C Blood Glucose Tests -.388*** Disease Duration.408*** Depressive Symptoms.268** Blood Glucose Tests Child Age -.266** Depressive Symptoms *** p <.001 ** p <.01

55 Differences by Depressive Symptoms No Depressive Symptoms Depressive Symptoms t-value p-value # of Tests A1C (Visit 1) ** p <.01

56 Summary Adherence to blood glucose testing regimen varies in children with type 1 diabetes As expected, lower A1C associated with better blood glucose testing adherence Nearly 1/3 of caregivers of children with type 1 diabetes exhibited depressive symptoms Increased depressive symptoms associated with poorer glycemic control As children get older, adherence gets worse.

57 Future Research What is contributing to higher rates of depressive symptoms in caregivers of children with type 1 diabetes? Does poor glycemic control lead to caregiver depression or does caregiver depression lead to poor glycemic control? Development of interventions

58 Acknowledgements Special thanks to the families who participated in this study. Medical staff at the diabetes clinic at Shands Hospital and at Dr. Deeb s diabetes clinic