Barriers and Motivations to Provide Dental Care to Adult Patients with Movement Disorders.

Patients with movement disorders, like Parkinson's and Huntington's diseases, tend to have poor oral health. Although contributing factors have been proposed, the willingness and ability of dentists to treat this patient population are still unknown. Our objective is to understand the current barriers and motivations of dentists to treat this patient population as a path to improved care and quality of life. A total of 176 dentists in Texas were surveyed through a structured questionnaire which contained both closed and open-ended questions. Nearly 30% of participants reported having no barriers to treating these patients and 26.7% reported that no such patients have visited their practice. Barriers reported included lack of education on the topic (17.6%) and longer appointments than average (14.8%). A main motivation to treat these patients was more training and education on the subject (38.6%). Poor oral health in patients with movement disorders may not be due to barriers encountered by dentists, but rather encountered by patients, such as access to and use of dental treatment. General dentists are willing to provide care for adult patients with movement disorders and continuing education for these providers is preferred over referral to a specialist.

Oral Factors That Impact the Oral Microbiota in Parkinson's Disease.

Patients with Parkinson's disease (PD) are at increased risk of aspiration pneumonia, their primary cause of death. Their oral microbiota differs from healthy controls, exacerbating this risk. Our goal was to explore if poor oral health, poor oral hygiene, and dysphagia status affect the oral microbiota composition of these patients. In this cross-sectional case-control study, the oral microbiota from hard and soft tissues of patients with PD (n = 30) and age-, gender-, and education-matched healthy controls (n = 30) was compared using 16S rRNA gene sequencing for bacterial identification. Study participants completed dietary, oral hygiene, drooling, and dysphagia questionnaires, and an oral health screening. Significant differences in soft tissue beta-diversity (p < 0.005) were found, and a higher abundance of opportunistic oral pathogens was detected in patients with PD. Factors that significantly influenced soft tissue beta-diversity and microbiota composition include dysphagia, drooling (both p < 0.05), and salivary pH (p < 0.005). Thus, patients with PD show significant differences in their oral microbiota compared to the controls, which may be due, in part, to dysphagia, drooling, and salivary pH. Understanding factors that alter their oral microbiota could lead to the development of diagnostic and treatment strategies that improve the quality of life and survivability of these patients.

Oral Health Assessment by Lay Personnel for Older Adults.

Oral health is an often-undervalued contributor to overall health. The literature, however, underscores the myriad of systemic diseases influenced by oral health, including type II diabetes, heart disease, and atherosclerosis. Thus, assessments of oral health, called oral screenings, have a significant role in assessing risk of disease, managing disease, and even improving disease by oral care. Here we present a method to assess oral health quickly and consistently across time. The protocol is simple enough for non-oral health professionals such as students, family, and caregivers. Useful for any age of patient, the method is particularly key for older individuals who are often at risk of inflammation and chronic disease. Components of the method include existing oral health assessment scales and inventories, which are combined to produce a comprehensive assessment of oral health. Thus, oral characteristics assessed include intraoral and extraoral structures, soft and hard tissues, natural and artificial teeth, plaque, oral functions such as swallowing, and the impact this oral health status has on the patient's quality of life. Advantages of this method include its inclusion of measures and perceptions of both the observer and patient, and its ability to track changes in oral health over time. Results acquired are quantitative totals of questionnaire and oral screening items, which can be summed for an oral health status score. The scores of successive oral screenings can be used to track the progression of oral health across time and guide recommendations for both oral and overall health care.

A role for autophagy in long-term spatial memory formation in male rodents.

A hallmark of long-term memory formation is the requirement for protein synthesis. Administration of protein synthesis inhibitors impairs long-term memory formation without influencing short-term memory. Rapamycin is a specific inhibitor of target of rapamycin complex 1 (TORC1) that has been shown to block protein synthesis and impair long-term memory. In addition to regulating protein synthesis, TORC1 also phosphorylates Unc-51-like autophagy activating kinase-1 (Ulk-1) to suppress autophagy. As autophagy can be activated by rapamycin (and rapamycin inhibits long-term memory), our aim was to test the hypothesis that autophagy inhibitors would enhance long-term memory. To examine if learning alters autophagosome number, we used male reporter mice carrying the GFP-LC3 transgene. Using these mice, we observed that training in the Morris water maze task increases the number of autophagosomes, a finding contrary to our expectations. For learning and memory studies, male Long Evans rats were used due to their relatively larger size (compared to mice), making it easier to perform intrahippocampal infusions in awake, moving animals. When the autophagy inhibitors 3-methyladenine (3-MA) or Spautin-1 were administered bilaterally into the hippocampii prior to training in the Morris water maze task, the drugs did not alter learning. In contrast, when memory was tested 24 hours later by a probe trial, significant impairments were observed. In addition, intrahippocampal infusion of an autophagy activator peptide (TAT-Beclin-1) improved long-term memory. These results indicate that autophagy is not necessary for learning, but is required for long-term memory formation.

Parkinson's Disease Oral Health Module: Interprofessional Coordination of Care.

Introduction: Patients with Parkinson's disease (PD) suffer progressive neurodegeneration and experience motor and nonmotor symptoms. Oropharyngeal dysfunctions are increasingly recognized as nonmotor PD symptoms that negatively impact a patient's quality of life. This module was primarily created to update dental health professionals and educate dental students on the oral health needs of patients with PD, with an emphasis on interprofessional collaboration and evidence-based dentistry. The module may also benefit other health professionals from different disciplines working with patients with PD. Methods: The module was developed to be delivered in one 55-minute large-group session followed by a short assessment and case study discussion. Associated materials include PowerPoint slides with transcript, a narrated video version of the PowerPoint lecture, a quiz, and the case study. Thirty-four first-year dental students were invited to watch the narrated presentation, complete a pre-/postsurvey, and take the quiz. Results: All participants agreed dental schools should provide education regarding oral health in patients with neurological disorders, as only 29% of them had previously taken a related class. After watching the presentation, students reported that most of the information was new content and that the difficulty level met their expectations. All students reported that the lecture increased their interest in interprofessional collaboration. In a quiz taken immediately after the presentation, the class average grade was 82.7, with 94% of the class passing the quiz with a grade of 70 or more. Discussion: Educating dental professionals regarding care of patients with PD must emphasize interprofessional collaborations among health care providers.

Incorporating oral health into interprofessional care teams for patients with Parkinson's disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder that primarily affects the motor system. However, non-motor symptoms such as cognitive, autonomic, sleep-related and sensory dysfunctions are often reported. A subgroup of non-motor symptoms, oropharyngeal problems, also affects these patients in ways that greatly deteriorate quality of life. Each patient may develop a different set of non-motor symptoms, making interprofessional collaboration among health care providers a must to treat patients with PD. In this review, we argue that dental health professionals must be included in this interprofessional health care team. Patients with PD are at a higher risk for developing oral health problems that can exacerbate or be exacerbated by other non-motor symptoms, such as mental health and dysphagia This accelerates decline in quality of life and even increases the risk of death by aspiration pneumonia. Dentists can create preventive oral health plans as soon as a diagnosis is made and promptly treat a patient's dental problems, preventing them from affecting other health areas. We describe major oral health concerns and how health professionals and dentists can participate and collaborate to improve the health of patients with PD.

Strategies to improve dental health in elderly patients with cognitive impairment: A systematic review.

BACKGROUND: Cognitive impairment is the gradual loss of one's ability to learn, remember, pay attention, and make decisions. Cognitively impaired elderly people are a challenging patient population for dental health care professionals and may be at higher risk of developing oral health diseases. The authors systematically reviewed interventions effective at improving dental health in patients with cognitive impairment and described research gaps remaining. TYPES OF STUDIES REVIEWED: In a comprehensive search of multiple databases, the authors identified 2,255 studies published in the English language from 1995 through March 2016. The authors included studies if the investigators evaluated oral health measures after an intervention in patients 65 years or older with cognitive impairment or dementia. Nine full-text articles met the criteria for inclusion. RESULTS: Only 1 study was a randomized control trial, whereas all others lacked appropriate controls. Investigators studied the effects of dental treatments, battery-powered devices for oral hygiene, and training of care staff members. Most interventions improved some aspect of the oral health of patients with dementia, and results were more pronounced when patients required assistance while performing oral hygiene tasks or had poor oral health at baseline. CONCLUSIONS AND PRACTICAL IMPLICATIONS: A basic care plan for patients with dementia should, at the minimum, match prevention strategies recommended for healthy elderly patients. Dental health care professionals should promote oral hygiene education for caregivers for elderly patients with cognitive impairment. There is a wide gap in knowledge regarding effective methods specifically to improve oral health in patients with dementia.

Traumatic brain injury decreases AMP-activated protein kinase activity and pharmacological enhancement of its activity improves cognitive outcome.

Prolonged metabolic suppression in the brain is a well-characterized secondary pathology of both experimental and clinical traumatic brain injury (TBI). AMP-activated kinase (AMPK) acts as a cellular energy sensor that, when activated, regulates various metabolic and catabolic pathways to decrease ATP consumption and increase ATP synthesis. As energy availability after TBI is suppressed, we questioned if increasing AMPK activity after TBI would improve cognitive outcome. TBI was delivered using the electromagnetic controlled cortical impact model on male Sprague-Dawley rats (275-300 g) and C57BL/6 mice (20-25 g). AMPK activity within the injured parietal cortex and ipsilateral hippocampus was inferred by western blots using phospho-specific antibodies. The consequences of acute manipulation of AMPK signaling on cognitive function were assessed using the Morris water maze task. We found that AMPK activity is decreased as a result of injury, as indicated by reduced AMPK phosphorylation and corresponding changes in the phosphorylation of its downstream targets: ribosomal protein S6 and Akt Substrate of 160 kDa (AS160). Increasing AMPK activity after injury using the drugs 5-amino-1-ß-d-ribofuranosyl-imidazole-4-carboxamide or metformin did not affect spatial learning, but significantly improved spatial memory. Taken together, our results suggest that decreased AMPK activity after TBI may contribute to the cellular energy crisis in the injured brain, and that AMPK activators may have therapeutic utility. Increased phosphorylation of Thr172 activates AMP-activated protein kinase (AMPK) under conditions of low cellular energy availability. This leads to inhibition of energy consuming, while activating energy generating, processes. Hill et al., present data to indicate that TBI decreases Thr172 phosphorylation and that its stimulation by pharmacological agents offers neuroprotection and improves memory. These results suggest that decreased AMPK phosphorylation after TBI incorrectly signals the injured brain that excess energy is available, thereby contributing to the cellular energy crisis and memory impairments.

Intrahippocampal glutamine administration inhibits mTORC1 signaling and impairs long-term memory.

The mechanistic Target of Rapamycin Complex 1 (mTORC1), a key regulator of protein synthesis and cellular growth, is also required for long-term memory formation. Stimulation of mTORC1 signaling is known to be dependent on the availability of energy and growth factors, as well as the presence of amino acids. In vitro studies using serum- and amino acid-starved cells have reported that glutamine addition can either stimulate or repress mTORC1 activity, depending on the particular experimental system that was used. However, these experiments do not directly address the effect of glutamine on mTORC1 activity under physiological conditions in nondeprived cells in vivo. We present experimental results indicating that intrahippocampal administration of glutamine to rats reduces mTORC1 activity. Moreover, post-training administration of glutamine impairs long-term spatial memory formation, while coadministration of glutamine with leucine had no influence on memory. Intracellular recordings in hippocampal slices showed that glutamine did not alter either excitatory or inhibitory synaptic activity, suggesting that the observed memory impairments may not result from conversion of glutamine to either glutamate or GABA. Taken together, these findings indicate that glutamine can decrease mTORC1 activity in the brain and may have implications for treatments of neurological diseases associated with high mTORC1 signaling.

Prolonging the survival of Tsc2 conditional knockout mice by glutamine supplementation.

The genetic disease tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by loss of function mutations in either TSC1 (hamartin) or TSC2 (tuberin), which serve as negative regulators of mechanistic target of rapamycin complex 1 (mTORC1) activity. TSC patients exhibit developmental brain abnormalities and tuber formations that are associated with neuropsychological and neurocognitive impairments, seizures and premature death. Mechanistically, TSC1 and TSC2 loss of function mutations result in abnormally high mTORC1 activity. Thus, the development of a strategy to inhibit abnormally high mTORC1 activity may have therapeutic value in the treatment of TSC. mTORC1 is a master regulator of growth processes, and its activity can be reduced by withdrawal of growth factors, decreased energy availability, and by the immunosuppressant rapamycin. Recently, glutamine has been shown to alter mTORC1 activity in a TSC1-TSC2 independent manner in cells cultured under amino acid- and serum-deprived conditions. Since starvation culture conditions are not physiologically relevant, we examined if glutamine can regulate mTORC1 in non-deprived cells and in a murine model of TSC. Our results show that glutamine can reduce phosphorylation of S6 and S6 kinase, surrogate indicators of mTORC1 activity, in both deprived and non-deprived cells, although higher concentrations were required for non-deprived cultures. When administered orally to TSC2 knockout mice, glutamine reduced S6 phosphorylation in the brain and significantly prolonged their lifespan. Taken together, these results suggest that glutamine supplementation can be used as a potential treatment for TSC.

Genetic activation of mTORC1 signaling worsens neurocognitive outcome after traumatic brain injury.

Although the mechanisms that contribute to the development of traumatic brain injury (TBI)-related deficits are not fully understood, it has been proposed that altered energy utilization may be a contributing factor. The tuberous sclerosis complex, a heterodimer composed of hamartin/Tsc-1 and tuberin/Tsc-2, is a critical regulatory node that integrates nutritional and growth signals to govern energy using processes by regulating the activity of mechanistic Target of Rapamycin complex 1 (mTORC1). mTORC1 activation results in enhanced protein synthesis, an energy consuming process. We show that mice that have a heterozygous deletion of Tsc2 exhibit elevated basal mTORC1 activity in the cortex and the hippocampus while still exhibiting normal motor and neurocognitive functions. In addition, a mild closed head injury (mCHI) that did not activate mTORC1 in wild-type mice resulted in a further increase in mTORC1 activity in Tsc2(+/KO) mice above the level of activity observed in uninjured Tsc2(+/KO) mice. This enhanced level of increased mTORC1 activity was associated with worsened cognitive function as assessed using the Morris water maze and context discrimination tasks. These results suggest that there is a threshold of increased mTORC1 activity after a TBI that is detrimental to neurobehavioral performance, and interventions to inhibit excessive mTORC1 activation may be beneficial to neurocognitive outcome.

Repeated mild closed head injury impairs short-term visuospatial memory and complex learning.

Concussive force can cause neurocognitive and neurobehavioral dysfunction by inducing functional, electrophysiological, and/or ultrastructural changes within the brain. Although concussion-triggered symptoms typically subside within days to weeks in most people, in 15%-20% of the cases, symptomology can continue beyond this time point. Problems with memory, attention, processing speed, and cognitive flexibility (e.g., problem solving, conflict resolution) are some of the prominent post-concussive cognitive symptoms. Repeated concussions (with loss or altered consciousness), which are common to many contact sports, can exacerbate these symptoms. The pathophysiology of repeated concussions is not well understood, nor is an effective treatment available. In order to facilitate drug discovery to treat post-concussive symptoms (PCSs), there is a need to determine if animal models of repeated mild closed head injury (mCHI) can mimic the neurocognitive and histopathological consequences of repeated concussions. To this end, we employed a controlled cortical impact (CCI) device to deliver a mCHI directly to the skull of mice daily for 4 days, and examined the ensuing neurological and neurocognitive functions using beam balance, foot-fault, an abbreviated Morris water maze test, context discrimination, and active place avoidance tasks. Repeated mCHI exacerbated vestibulomotor, motor, short-term memory and conflict learning impairments as compared to a single mCHI. Learning and memory impairments were still observed in repeated mCHI mice when tested 3 months post-injury. Repeated mCHI also reduced cerebral perfusion, prolonged the inflammatory response, and in some animals, caused hippocampal neuronal loss. Our results show that repeated mCHI can reproduce some of the deficits seen after repeated concussions in humans and may be suitable for drug discovery studies and translational research.

The differential effects of prenatal and/or postnatal rapamycin on neurodevelopmental defects and cognition in a neuroglial mouse model of tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is caused by heterozygous mutations in either the TSC1 (hamartin) or the TSC2 (tuberin) gene. Among the multisystemic manifestations of TSC, the neurodevelopmental features cause the most morbidity and mortality, presenting a considerable clinical challenge. Hamartin and tuberin form a heterodimer that inhibits the mammalian target of rapamycin complex 1 (mTORC1) kinase, a major cellular regulator of protein translation, cell growth and proliferation. Hyperactivated mTORC1 signaling, an important feature of TSC, has prompted a number of preclinical and clinical studies with the mTORC1 inhibitor rapamycin. Equally exciting is the prospect of treating TSC in the perinatal period to block the progression of brain pathologies and allow normal brain development to proceed. We hypothesized that low-dose rapamycin given prenatally and/or postnatally in a well-established neuroglial (Tsc2-hGFAP) model of TSC would rescue brain developmental defects. We developed three treatment regimens with low-dose intraperitoneal rapamycin (0.1 mg/kg): prenatal, postnatal and pre/postnatal (combined). Combined rapamycin treatment resulted in almost complete histologic rescue, with a well-organized cortex and hippocampus almost identical to control animals. Other treatment regimens yielded less complete, but significant improvements in brain histology. To assess how treatment regimens affected cognitive function, we continued rapamycin treatment after weaning and performed behavioral testing. Surprisingly, the animals treated with the combined therapy did not perform as well as postnatally-treated animals in learning and memory tasks. These results have important translational implications in the optimization of the timing and dosage of rapamycin treatment in TSC affected children.

Evidence for light perception in a bioluminescent organ.

Here we show that bioluminescent organs of the squid Euprymna scolopes possess the molecular, biochemical, and physiological capability for light detection. Transcriptome analyses revealed expression of genes encoding key visual transduction proteins in light-organ tissues, including the same isoform of opsin that occurs in the retina. Electroretinograms demonstrated that the organ responds physiologically to light, and immunocytochemistry experiments localized multiple proteins of visual transduction cascades to tissues housing light-producing bacterial symbionts. These data provide evidence that the light-organ tissues harboring the symbionts serve as extraocular photoreceptors, with the potential to perceive directly the bioluminescence produced by their bacterial partners.

Elevated levels of angiostatin in effusions from patients with malignant disease.

The aim of this study was to determine the presence of angiostatin in ascitic and pleural effusions from cancer patients, as well as of metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA), both involved in angiostatin generation in in vitro models. Ascitic fluids, pleural exudates, and sera from 21 cancer patients were analyzed for the presence of angiostatin by western blot, whereas gelatinases MMP-2 and MMP-9, and uPA were evaluated by zymography. Our study revealed elevated levels of angiostatin in effusions of cancer patients, contrasting with mostly intermediate levels in less than half of their sera, and undetectable levels in normal sera. Despite the observation of enhanced levels of HMW-uPA and MMP-2 in malignant effusions from cancer patients, their analysis in individual samples showed no association between angiostatin presence and the enzymes, suggesting that the latter would not play an unimportant role, if any, in in vivo generation of angiostatin.