Protocol for Expression of Murine Milk Using Modified Human Breast Pump Parts

Understanding the nutritional and immunomodulatory components of breast milk is crucial to developing novel mechanisms to optimize neonatal health. Here, we present a protocol to express and isolate murine milk in sufficient quantities for further analysis of components and bioactivity. We describe steps for separating dams from pups, administering intraperitoneal anesthetic and oxytocin, and expressing milk using a minimally modified and readily available commercial breast pump parts. For complete details on the use and execution of this protocol, please refer to Meyer et al. (2022)

Protocol for Expression of Murine Milk Using Modified Human Breast Pump Parts

Understanding the nutritional and immunomodulatory components of breast milk is crucial to developing novel mechanisms to optimize neonatal health. Here, we present a protocol to express and isolate murine milk in sufficient quantities for further analysis of components and bioactivity. We describe steps for separating dams from pups, administering intraperitoneal anesthetic and oxytocin, and expressing milk using a minimally modified and readily available commercial breast pump parts. For complete details on the use and execution of this protocol, please refer to Meyer et al. (2022).

Effects of oxytocin on human aggression

EFFECTS OF OXYTOCIN ON HUMAN AGGRESSION Joseph Louis Alcorn III, B.S. Advisory Professor: Scott D. Lane, Ph.D. Human interaction is comprised of common, yet complex, behaviors and the outcomes of these social behaviors can beneficially or detrimentally impact individual and public health. One social behavior that can have profound detrimental outcomes is aggression. Aggression is a class of social behavior that is particularly prevalent in individuals with antisocial personality disorder (ASPD) and comorbid substance use disorder (SUD). Aggression in these individuals can manifest at maladaptive levels that place considerable burdens on public health and communities. Therefore, understanding the neurobehavioral underpinnings of aggression holds substantial merit. The goal of this project was to examine the effects of this oxytocin (OT) on human aggression. Considerable work has demonstrated that OT engenders the promotion of affiliative social behaviors that are mutually beneficial (or prosocial) between two individuals. Aggression is characterized, in part, by social behaviors that are antisocial (which are opposite to prosocial behavior). The hypothesis was that acute administration of OT would reduce the frequency of human aggression. This hypothesis was tested in both individuals with comorbid ASPD and SUD, and healthy volunteers. This project employed a well-established laboratory measure of human aggression, the Point Subtraction Aggression Paradigm, which measures changes in the frequency of aggressive behavior. In ASPD+SUD individuals there was no significant reduction in aggressive behavior following OT administration. However, there were non-systematic individual differences on aggressive behavior following OT dosing, which suggested modulation of aggressive behavior by OT. In healthy volunteers there was no significant effect of OT dose on aggressive behavior. However, in healthy volunteers, an examination of individual differences focused on antisocial personality traits revealed that aggressive behavior under OT was positively correlated with interpersonal manipulation and anger (Pearson’s r = 0.57). Healthy volunteers with higher scores of interpersonal manipulation and anger actually showed an increase in their aggressive behavior following OT administration. In both ASPD+SUD individual and healthy volunteers, the hypothesis that OT would decrease human aggression was not supported. The experiments of this dissertation revealed substantial individual differences in aggression following OT administration, which is important for future research in examining the therapeutic efficacy of OT for the management of aggression in antisocial and substance abuse populations

Comparing Cigarette-Cue Attentional Bias Between People With HIV/Aids and People With Opioid Use Disorder Who Smoke

BACKGROUND: Special populations like people living with HIV/AIDS (PLWHA) and people with opioid use disorder (OUD) smoke tobacco cigarettes at rates three to four times greater than the general population. Patients with tobacco use disorder exhibit attentional bias (AB) for cigarette cues. Eye tracking can quantify this bias by measuring fixation time (FT) on cigarette and matched neutral cues, to calculate an AB score. Although previous studies have measured this bias in people who smoke without any other comorbid conditions, no study, to our knowledge, has measured or compared this bias in special populations. METHODS: We performed exploratory analyses on eye tracking data collected in two separate randomized clinical trials (RCTs) (NCT05049460, NCT05295953). We compared FT and cigarette-cue AB score (measured by subtracting FT on neutral cues from FT on cigarette cues) between PLWHA and people with OUD who smoke, using a visual probe task and Tobii Pro Fusion eye tracker. We used two cigarette cue types, one encompassing people smoking cigarettes and the other consisting of cigarette paraphernalia. We used two cue presentation times, 1000 and 2000 milliseconds (ms). RESULTS: Cues of people smoking cigarettes elicited greater AB than cues of cigarette paraphernalia across both subject groups when cues were presented for 2000 ms, but not 1000 ms. PLWHA who smoke exhibited greater AB for cues of people smoking cigarettes than cigarette paraphernalia when presented for 2000 ms compared to people with OUD who smoke. CONCLUSION: We use cigarette-cue AB to quantify craving and cigarette consumption in two populations smoking at elevated rates. The addition of social cues potentiates cigarette cue AB, based on cue type and stimulus presentation time. Understanding the neurobiology of this relationship can help design novel smoking cessation treatments that target AB and prevent relapse in these populations with suboptimal response to smoking cessation treatments. TRIAL REGISTRATION: Clinical trials that provided the data for post hoc analyses are NCT05049460 and NCT05295953

A Pilot Investigation of Acute Inhibitory Control Training in Cocaine Users

Background—Disrupted response inhibition and presence of drug-cue attentional bias in cocaine-using individuals have predicted poor treatment outcomes. Inhibitory control training could help improve treatment outcomes by strengthening cognitive control. This pilot study assessed the effects of acute inhibitory control training to drug- and non-drug-related cues on response inhibition performance and cocaine-cue attentional bias in cocaine-using individuals. Methods—Participants who met criteria for a cocaine-use disorder underwent five sessions of inhibitory control training to either non-drug-related cues (i.e., rectangles) or cocaine cues (n=10/condition) in a single day. Response inhibition and attentional bias were assessed prior to and following training using the stop-signal task and visual-probe task with eye tracking, respectively. Results—Training condition groups did not differ on demographics, inhibitory control training performance, response inhibition, or cocaine-cue attentional bias. Response inhibition performance improved as a function of inhibitory control training in both conditions. Cocaine-cue attentional bias was observed, but did not change as a function of inhibitory control training in either condition. Conclusions—Response inhibition in cocaine-using individuals was augmented by acute inhibitory control training, which may improve treatment outcomes through better behavioral inhibition. Future studies should investigate longer-term implementation of inhibitory control training, as well as combining inhibitory control training with other treatment modalities

Chop (Ddit3) Is Essential for D469del-COMP Retention and Cell Death in Chondrocytes in an Inducible Transgenic Mouse Model of Pseudoachondroplasia

Cartilage oligomeric matrix protein (COMP), a secreted glycoprotein synthesized by chondrocytes, regulates proliferation and type II collagen assembly. Mutations in the COMP gene cause pseudoachondroplasia and multiple epiphyseal dysplasia. Previously, we have shown that expression of D469del-COMP in transgenic mice causes intracellular retention of D469del-COMP, thereby recapitulating pseudoachondroplasia chondrocyte pathology. This inducible transgenic D469del-COMP mouse is the only in vivo model to replicate the critical cellular and clinical features of pseudoachondroplasia. Here, we report developmental studies of D469del-COMP-induced chondrocyte pathology from the prenatal period to adolescence. D469del-COMP retention was limited prenatally and did not negatively affect the growth plate until 3 weeks after birth. Results of immunostaining, transcriptome analysis, and qRT-PCR suggest a molecular model in which D469del-COMP triggers apoptosis during the first postnatal week. By 3 weeks (when most chondrocytes are retaining D469del-COMP), inflammation, oxidative stress, and DNA damage contribute to chondrocyte cell death by necroptosis. Importantly, by crossing the D469del-COMP mouse onto a Chop null background (Ddit3 null), thereby eliminating Chop, the unfolded protein response was disrupted, thus alleviating both D469del-COMP intracellular retention and premature chondrocyte cell death. Chop therefore plays a significant role in processes that mediate D469del-COMP retention. Taken together, these results suggest that there may be an optimal window before the induction of significant D469del-COMP retention during which endoplasmic reticulum stress could be targeted

Surfactant Protein a Attenuates Generalized and Localized Neuroinflammation in Neonatal Mice

Surfactant protein A (SP-A) has important roles in innate immunity and modulation of pulmonary and extrapulmonary inflammation. Given SP-A has been detected in rat and human brain, we sought to determine if SP-A has a role in modulating inflammation in the neonatal mouse brain. Neonatal wildtype (WT) and SP-A-deficient (SP-

Surfactant Protein a Attenuates Generalized and Localized Neuroinflammation in Neonatal Mice

Surfactant protein A (SP-A) has important roles in innate immunity and modulation of pulmonary and extrapulmonary inflammation. Given SP-A has been detected in rat and human brain, we sought to determine if SP-A has a role in modulating inflammation in the neonatal mouse brain. Neonatal wildtype (WT) and SP-A-deficient (SP-A−/−) mice were subjected to three models of brain inflammation: systemic sepsis, intraventricular hemorrhage (IVH) and hypoxic-ischemic encephalopathy (HIE). Following treatment, RNA was isolated from brain tissue and expression of cytokine and SP-A mRNA was determined by real-time quantitative RT-PCR analysis. In the sepsis model, expression of most cytokine mRNAs was significantly increased in brains of WT and SP-A−/− neonates with significantly greater expression of all cytokine mRNA levels in SP-A−/− mice compared to WT. In the IVH model, expression of all cytokine mRNAs was significantly increased in WT and SP-A−/− mice and levels of cytokine mRNAs were significantly increased in SP-A−/− mice compared to WT. In the HIE model, only TNF-α mRNA levels were significantly increased in WT brain tissue while most cytokine mRNAs were significantly increased in SP-A−/− mice, and all cytokine mRNA levels were significantly higher in SP-A−/− mice compared to WT. SP-A mRNA was not detectable in brain tissue of adult WT mice nor of WT neonates subjected to the models. These results suggest that SP-A−/− neonatal mice subjected to models of neuroinflammation are more susceptible to generalized and localized neuroinflammation compared to WT mice, thus supporting the hypothesis that SP-A attenuates inflammation in neonatal mouse brain

RNAi Reduces Expression and Intracellular Retention of Mutant Cartilage Oligomeric Matrix Protein

Mutations in cartilage oligomeric matrix protein (COMP), a large extracellular glycoprotein expressed in musculoskeletal tissues, cause two skeletal dysplasias, pseudoachondroplasia and multiple epiphyseal dysplasia. These mutations lead to massive intracellular retention of COMP, chondrocyte death and loss of growth plate chondrocytes that are necessary for linear growth. In contrast, COMP null mice have only minor growth plate abnormalities, normal growth and longevity. This suggests that reducing mutant and wild-type COMP expression in chondrocytes may prevent the toxic cellular phenotype causing the skeletal dysplasias. We tested this hypothesis using RNA interference to reduce steady state levels of COMP mRNA. A panel of shRNAs directed against COMP was tested. One shRNA (3B) reduced endogenous and recombinant COMP mRNA dramatically, regardless of expression levels. The activity of the shRNA against COMP mRNA was maintained for up to 10 weeks. We also demonstrate that this treatment reduced ER stress. Moreover, we show that reducing steady state levels of COMP mRNA alleviates intracellular retention of other extracellular matrix proteins associated with the pseudoachondroplasia cellular pathology. These findings are a proof of principle and the foundation for the development of a therapeutic intervention based on reduction of COMP expression