Western diet consumption impairs memory function via dysregulated hippocampus acetylcholine signaling.

Western diet (WD) consumption during early life developmental periods is associated with impaired memory function, particularly for hippocampus (HPC)-dependent processes. We developed an early life WD rodent model associated with long-lasting HPC dysfunction to investigate the neurobiological mechanisms mediating these effects. Rats received either a cafeteria-style WD (ad libitum access to various high-fat/high-sugar foods; CAF) or standard healthy chow (CTL) during the juvenile and adolescent stages (postnatal days 26-56). Behavioral and metabolic assessments were performed both before and after a healthy diet intervention period beginning at early adulthood. Results revealed HPC-dependent contextual episodic memory impairments in CAF rats that persisted despite the healthy diet intervention. Given that dysregulated HPC acetylcholine (ACh) signaling is associated with memory impairments in humans and animal models, we examined protein markers of ACh tone in the dorsal HPC (HPCd) in CAF and CTL rats. Results revealed significantly lower protein levels of vesicular ACh transporter in the HPCd of CAF vs. CTL rats, indicating chronically reduced ACh tone. Using intensity-based ACh sensing fluorescent reporter (iAChSnFr) in vivo fiber photometry targeting the HPCd, we next revealed that ACh release during object-contextual novelty recognition was highly predictive of memory performance and was disrupted in CAF vs. CTL rats. Neuropharmacological results showed that alpha 7 nicotinic ACh receptor agonist infusion in the HPCd during training rescued memory deficits in CAF rats. Overall, these findings reveal a functional connection linking early life WD intake with long-lasting dysregulation of HPC ACh signaling, thereby identifying an underlying mechanism for WD-associated memory impairments.

Current monitoring and treatment for anal intraepithelial neoplasms.

Anal intraepithelial neoplasms (AIN) are precursors to anal cancer. To date, there is not a significant body of literature to support screening, monitoring, and treatment of these precursor lesions, particularly in high risk populations. This review will detail the current monitoring and indications for treatment of such lesions, with the goal of preventing progression to invasive cancer.

Telesurgical Assessment: Using Smartphone Messaging to Efficiently Manage Postoperative Wounds.

Background: Telemedicine is an evolving field of interactions between physicians and patients remotely. Health care delivery, patient satisfaction, adherence, earlier diagnosis, increased access, and cost reduction are all areas that telemedicine has potential influence. One focus involves the use of photos in wound assessment. Today, many patients' smartphones can capture high-quality digital photographs, which can easily be transmitted. Postoperative patients are an ideal population for this, as they have a certain level of uncertainty with regard to the healing course, which can often lead to patients seeking out care in unnecessarily costly settings. These visits can lead to inefficient use of health care resources, especially when a telesurgical assessment (TSA) could provide appropriate care more efficiently. Objective: We present data collected from a series of patients who received a TSA to demonstrate the potential benefits of incorporating TSA into postoperative wound care. Methods/Clinical Presentation: Patients who underwent a procedure and contacted their surgeon within 2 weeks with concerns received a TSA, which included a discussion as well as photographs through smartphone. Their surgeon then determined further treatment steps, if any. Results: We experienced that 85% of patients did not require emergent treatment for their concerns, 46% were prescribed medications, whereas 39% of patients did not require any intervention. Conclusion: Our results show that TSAs alleviated patient concerns and provide resolutions, while saving resources and increasing satisfaction. Incorporating aspects of telemedicine into outpatient practice could be valuable, especially with postoperative wound checks.

Hypothalamic melanin-concentrating hormone neurons integrate food-motivated appetitive and consummatory processes in rats.

The lateral hypothalamic area (LHA) integrates homeostatic processes and reward-motivated behaviors. Here we show that LHA neurons that produce melanin-concentrating hormone (MCH) are dynamically responsive to both food-directed appetitive and consummatory processes in male rats. Specifically, results reveal that MCH neuron Ca2+ activity increases in response to both discrete and contextual food-predictive cues and is correlated with food-motivated responses. MCH neuron activity also increases during eating, and this response is highly predictive of caloric consumption and declines throughout a meal, thus supporting a role for MCH neurons in the positive feedback consummatory process known as appetition. These physiological MCH neural responses are functionally relevant as chemogenetic MCH neuron activation promotes appetitive behavioral responses to food-predictive cues and increases meal size. Finally, MCH neuron activation enhances preference for a noncaloric flavor paired with intragastric glucose. Collectively, these data identify a hypothalamic neural population that orchestrates both food-motivated appetitive and intake-promoting consummatory processes.

Western diet consumption impairs memory function via dysregulated hippocampus acetylcholine signaling.

Western diet (WD) consumption during development yields long-lasting memory impairments, yet the underlying neurobiological mechanisms remain elusive. Here we developed an early life WD rodent model to evaluate whether dysregulated hippocampus (HPC) acetylcholine (ACh) signaling, a pathology associated with memory impairment in human dementia, is causally-related to WD-induced cognitive impairment. Rats received a cafeteria-style WD (access to various high-fat/high-sugar foods; CAF) or healthy chow (CTL) during the juvenile and adolescent periods (postnatal days 26-56). Behavioral, metabolic, and microbiome assessments were performed both before and after a 30-day healthy diet intervention beginning at early adulthood. Results revealed CAF-induced HPC-dependent contextual episodic memory impairments that persisted despite healthy diet intervention, whereas CAF was not associated with long-term changes in body weight, body composition, glucose tolerance, anxiety-like behavior, or gut microbiome. HPC immunoblot analyses after the healthy diet intervention identified reduced levels of vesicular ACh transporter in CAF vs. CTL rats, indicative of chronically reduced HPC ACh tone. To determine whether these changes were functionally related to memory impairments, we evaluated temporal HPC ACh binding via ACh-sensing fluorescent reporter in vivo fiber photometry during memory testing, as well as whether the memory impairments could be rescued pharmacologically. Results revealed dynamic HPC ACh binding during object-contextual novelty recognition was highly predictive of memory performance and was disrupted in CAF vs. CTL rats. Further, HPC alpha-7 nicotinic receptor agonist infusion during consolidation rescued memory deficits in CAF rats. Overall, these findings identify dysregulated HPC ACh signaling as a mechanism underlying early life WD-associated memory impairments.

Ventral hippocampus neurons encode meal-related memory.

The ability to encode and retrieve meal-related information is critical to efficiently guide energy acquisition and consumption, yet the underlying neural processes remain elusive. Here we reveal that ventral hippocampus (HPCv) neuronal activity dynamically elevates during meal consumption and this response is highly predictive of subsequent performance in a foraging-related spatial memory task. Targeted recombination-mediated ablation of HPCv meal-responsive neurons impairs foraging-related spatial memory without influencing food motivation, anxiety-like behavior, or escape-mediated spatial memory. These HPCv meal-responsive neurons project to the lateral hypothalamic area (LHA) and single-nucleus RNA sequencing and in situ hybridization analyses indicate they are enriched in serotonin 2a receptors (5HT2aR). Either chemogenetic silencing of HPCv-to-LHA projections or intra-HPCv 5HT2aR antagonist yielded foraging-related spatial memory deficits, as well as alterations in caloric intake and the temporal sequence of spontaneous meal consumption. Collective results identify a population of HPCv neurons that dynamically respond to eating to encode meal-related memories.

Ventral hippocampus-lateral septum circuitry promotes foraging-related memory.

Remembering the location of a food or water source is essential for survival. Here, we reveal that spatial memory for food location is reflected in ventral hippocampus (HPCv) neuron activity and is impaired by HPCv lesion. HPCv mediation of foraging-related memory involves communication to the lateral septum (LS), as either reversible or chronic disconnection of HPCv-to-LS signaling impairs spatial memory retention for food or water location. This neural pathway selectively encodes appetitive spatial memory, as HPCv-LS disconnection does not affect spatial memory for escape location in a negative reinforcement procedure, food intake, or social and olfactory-based appetitive learning. Neural pathway tracing and functional mapping analyses reveal that LS neurons recruited during the appetitive spatial memory procedure are primarily GABAergic neurons that project to the lateral hypothalamus. Collective results emphasize that the neural substrates controlling spatial memory are outcome specific based on reinforcer modality.

Sexually Dimorphic Effects of a Western Diet on Brain Mitochondrial Bioenergetics and Neurocognitive Function.

A Western diet (WD), high in sugars and saturated fats, impairs learning and memory function and contributes to weight gain. Mitochondria in the brain provide energy for neurocognitive function and may play a role in body weight regulation. We sought to determine whether a WD alters behavior and metabolic outcomes in male and female rodents through impacting hippocampal and hypothalamic mitochondrial bioenergetics. Results revealed a sexually dimorphic macronutrient preference, where males on the WD consumed a greater percentage of calories from fat/protein and females consumed a greater percentage of calories from a sugar-sweetened beverage. Both males and females on a WD gained body fat and showed impaired glucose tolerance when compared to same-sex controls. Males on a WD demonstrated impaired hippocampal functioning and an elevated tendency toward a high membrane potential in hippocampal mitochondria. Comprehensive bioenergetics analysis of WD effects in the hypothalamus revealed a tissue-specific adaption, where males on the WD oxidized more fat, and females oxidized more fat and carbohydrates at peak energy demand compared to same-sex controls. These results suggest that adult male rats show a susceptibility toward hippocampal dysfunction on a WD, and that hypothalamic mitochondrial bioenergetics are altered by WD in a sex-specific manner.

Conditional Survival Analysis of Metastatic Colorectal Cancer Patients Living ≥24 Months: A Single Institutional Study.

OBJECTIVES: The survival of patients with metastatic colorectal cancer (CRC) has been increasing over recent decades due to improvements in chemotherapy and surgery. There is a need to refine prognostic information to more accurately predict survival as patients survive for any given length of time to assist multidisciplinary cancer management teams in treatment decisions. MATERIALS AND METHODS: We performed a single center retrospective analysis of patients treated with metastatic CRC (unresectable and resectable) who survived >24 months between 2005 and 2015 (N=155). Patient tumor and treatment related variables were collected. Overall survival (OS) estimates conditional on surviving >24 months were compared with actuarial survival estimates of a cohort of patients (33,104 resected, 39,382 unresected) from the National Cancer Database (NCDB). RESULTS: With a median follow-up of 44.2 months, the median OS of resected patients (n=86) was not reached. The median OS of unresected patients was 75.9 months. The conditional survival probabilities of living 1, 2, or 3 years longer after 24 months of survival are 92%, 72%, and 52%, respectively, in unresectable patients and 98%, 92%, and 89% in patients who were resected. The corresponding NCDB 1, 2, and 3 year actuarial survival was 38%, 20%, and 11% for unresected patients and 68%, 46%, and 32% for resected. CONCLUSIONS: These results indicate that CRC patients who survive 24 months with metastatic colorectal cancer have an excellent prognosis and surgery may be appropriate in a subset of patients initially deemed unresectable.

Bone marrow tolerance during postoperative chemotherapy in colorectal carcinomas.

BACKGROUND: This study seeks to quantify and compare bone marrow tolerance during postoperative chemotherapy therapy between rectal cancer vs. colon cancer patients. During rectal cancer treatment, patients receive neoadjuvant chemoradiation (CRT) irradiation which can exacerbate the hematologic toxicity (HT) via incidental irradiation of the pelvic bone marrow (PBM) during myelosuppressive postoperative chemotherapy. In contrast, colon cancer patients receive the same postoperative myelosuppressive chemotherapy but do not routinely receive preoperative chemoradiation therapy. This comparison will help elucidate the lasting myelosuppressive effects of incidental pelvic bone marrow (PBM) irradiation on rectal cancer patients during neoadjuvant preoperative chemoradiation therapy. METHODS: Rectal cancer patients treated with preoperative CRT followed by postoperative 5-Fluorouracil and oxaliplatin (OxF) chemotherapy (n=35) were compared to colon cancer patients who received only postoperative OxF chemotherapy (n=42). End points were ≥ grade 3 hematologic toxicity (HT3) or hematologic event (HE) defined as ≥ grade 2 HT and a dose reduction in OxF. Wilcoxon rank sum test tested continuous variables and Chi-squared test measured differences in categorical variables. HT3 and HE probability during postoperative chemotherapy was estimated with Kaplan-Meier curves and Cox regression analysis. RESULTS: During OxF chemotherapy, 40.0% (n=14) of rectal cancer patients experienced HT3 compared to 26.1% (n=11) of colon cancer patients (P=0.4). HE was experienced by 48% (n=17) of rectal cancer patients compared to 36% (n=15) of colon cancer patients (P=0.36). Rectal cancer patients were likelier to experience HT3 on multivariable cox regression analysis, controlling for several clinical covariates, with a hazard ratio (HR) of 2.49, [(95% CI: 1.02-6.02), P=0.045] than colon cancer patients. While rectal cancer patients were more likely to experience HE than colon cancer patients on multivariable Cox regression analysis with a HR of 1.8 (95% CI: 0.95-3.75), this only trended in statistical significance, P=0.07. CONCLUSIONS: Rectal cancer patients are more likely than colon cancer patients to experience hematologic toxicities impacting the tolerance of standard of care chemotherapeutics during adjuvant therapy. Focused PBM sparing during radiation therapy for rectal cancer patients may improve tolerance of myelosuppressive chemotherapeutic agents delivered in the postoperative setting.

U1 Adaptors Suppress the KRAS-MYC Oncogenic Axis in Human Pancreatic Cancer Xenografts.

Targeting KRAS and MYC has been a tremendous challenge in cancer drug development. Genetic studies in mouse models have validated the efficacy of silencing expression of both KRAS and MYC in mutant KRAS-driven tumors. We investigated the therapeutic potential of a new oligonucleotide-mediated gene silencing technology (U1 Adaptor) targeting KRAS and MYC in pancreatic cancer. Nanoparticles in complex with anti-KRAS U1 Adaptors (U1-KRAS) showed remarkable inhibition of KRAS in different human pancreatic cancer cell lines in vitro and in vivo As a nanoparticle-free approach is far easier to develop into a drug, we refined the formulation of U1 Adaptors by conjugating them to tumor-targeting peptides (iRGD and cRGD). Peptides coupled to fluorescently tagged U1 Adaptors showed selective tumor localization in vivo Efficacy experiments in pancreatic cancer xenograft models showed highly potent (>90%) antitumor activity of both iRGD and (cRGD)2-KRAS Adaptors. U1 Adaptors targeting MYC inhibited pancreatic cancer cell proliferation caused by apoptosis in vitro (40%-70%) and tumor regressions in vivo Comparison of iRGD-conjugated U1 KRAS and U1 MYC Adaptors in vivo revealed a significantly greater degree of cleaved caspase-3 staining and decreased Ki67 staining as compared with controls. There was no significant difference in efficacy between the U1 KRAS and U1 MYC Adaptor groups. Our results validate the value in targeting both KRAS and MYC in pancreatic cancer therapeutics and provide evidence that the U1 Adaptor technology can be successfully translated using a nanoparticle-free delivery system to target two undruggable genes in cancer. Mol Cancer Ther; 16(8); 1445-55. ©2017 AACR.