Cinnamaldehyde Protects against P. gingivalis Induced Intestinal Epithelial Barrier Dysfunction in IEC-6 Cells via the PI3K/Akt-Mediated NO/Nrf2 Signaling Pathway.

Porphyromonas gingivalis (Pg), a Gram-negative oral pathogen, promotes and accelerates periodontitis-associated gut disorders. Intestinal epithelial barrier dysfunction is crucial in the pathogenesis of intestinal and systemic diseases. In this study, we sought to elucidate the protective role of cinnamaldehyde (CNM, an activator of Nrf2) against P. gingivalis (W83) and Pg-derived lipopolysaccharide (Pg-LPS) induced intestinal epithelial barrier dysfunction via antioxidative mechanisms in IEC-6 cells. IEC-6 (ATCC, CRL-1592) cells were pretreated with or without CNM (100 µM), in the presence or absence of P. gingivalis (strain W83, 109 MOI) or Pg-LPS (1, 10, and 100 µg/mL), respectively, between 0-72 h time points by adopting a co-culture method. Intestinal barrier function, cytokine secretion, and intestinal oxidative stress protein markers were analyzed. P. gingivalis or Pg-LPS significantly (p < 0.05) increased reactive oxygen species (ROS) and malondialdehyde (MDA) levels expressing oxidative stress damage. Pg-LPS, as well as Pg alone, induces inflammatory cytokines via TLR-4 signaling. Furthermore, infection reduced Nrf2 and NAD(P)H quinone dehydrogenase 1 (NQO1). Interestingly, inducible nitric oxide synthase (iNOS) protein expression significantly (p < 0.05) increased with Pg-LPS or Pg infection, with elevated levels of nitric oxide (NO). CNM treatment suppressed both Pg- and Pg-LPS-induced intestinal oxidative stress damage by reducing ROS, MDA, and NO production. Furthermore, CNM treatment significantly upregulated the expression of tight junction proteins via increasing the phosphorylation levels of PI3K/Akt/Nrf2 suppressing inflammatory cytokines. CNM protected against Pg infection-induced intestinal epithelial barrier dysfunction by activating the PI3K/Akt-mediated Nrf2 signaling pathway in IEC-6 cells.

ChatGPT to Enhance Learning in Dental Education at a Historically Black Medical College.

The recent rise of powerful large language model (LLM)-based AI tools, exemplified by ChatGPT and Bard, poses a great challenge to contemporary dental education. It simultaneously offers a unique resource that potentially complements today's teaching and learning, where existing widely available learning resources have often fallen short. Although the LLM tools will shape both the clinical and educational aspects of dentistry profoundly, the didactic curricula, which primarily rely on lecture-based courses where instructors impart knowledge through presentations and discussions, need to be upgraded urgently. In this paper, we used dental course materials, syllabi, and textbooks adopted currently in the School of Dentistry (SOD) at Meharry Medical College to assess the potential utility and effectiveness of ChatGPT in dental education. We collected the responses of the chatbot to questions as well as students' interactions with it for assessment. Our results showed that ChatGPT can assist in dental essay writing and generate relevant content for dental students, in addition to other benefits. The limitations of ChatGPT were also discussed in the paper.

Investigating the relationship between dental cavities and protective factors among children aged 0-5 years.

The purpose of this study was to determine the protective factors that contribute to the prevention of children aged 0-5 years from developing dental cavities. The oral hygiene practices of 266 children aged 0-5 years were assessed through surveys administered from 2019 to 2022 to identify clinical, dietary, social and parental factors. The Partial Least Squares (PLS) Regression and Artificial Neuron Networks (ANN) Models were used to determine protective factors associated with the prevention of dental cavities in children. The race distribution of the children as identified by caregivers is as follows: (1) Black or African-American (53.4%); (2) Asian (25.9%); (3) White (18.4%); and (4) Native American (2.3%). We found behavioral protective factors to significantly affect the oral health outcome (cavities) among children aged 0-5 years (p < 0.05). We also found that children whose parents/caregivers flossed their teeth were less likely to develop cavities. In addition, children were least likely to have cavities if their parents/caregivers used toothpaste and mouthwash, avoided sharing chewed food, and refrained from drinking 100% juice. In contrast, children were more likely to obtain cavities if their parents/caregivers had a lower education level, rarely cleaned their teeth, and often consumed marijuana, cow or goat milk, juice drinks and sugary beverages. The education level of parents, and on the contrary, oral hygiene practices of the family, play a significant role in influencing the prevalence of cavities in children aged 0-5 years.

ChatGPT to enhance learning in dental education at a historically black medical college.

The recent rise of powerful large language model (LLM)-based AI tools, exemplified by ChatGPT and Bard, poses a great challenge to contemporary dental education while simultaneously offering a unique resource and approach that potentially complements today's teaching and learning, where existing widely available learning resources have often fallen short. Although both the clinical and educational aspects of dentistry will be shaped profoundly by the LLM tools, the didactic curricula, which primarily rely on lecture-based courses where instructors impart knowledge through presentations and discussions, need to be upgraded urgently. In this paper, we used dental course materials, syllabi, and textbooks adopted currently in the School of Dentistry (SOD) at Meharry Medical College to assess the potential utility and effectiveness of ChatGPT in dental education. We collected the responses of the chatbot to questions as well as students' interactions with it for assessment. Our results showed that ChatGPT can assist in dental essay writing and generate relevant content for dental students, in addition to other benefits. The limitations of ChatGPT were also discussed in the paper.

17ß-Estradiol Suppresses Gastric Inflammatory and Apoptotic Stress Responses and Restores nNOS-Mediated Gastric Emptying in Streptozotocin (STZ)-Induced Diabetic Female Mice.

Gastroparesis (Gp) is a severe complication of diabetes mellitus (DM) observed predominantly in women. It is characterized by abnormal gastric emptying (GE) without mechanical obstruction in the stomach. Nitric oxide (NO) is an inhibitory neurotransmitter produced by neuronal nitric oxide synthase (nNOS). It plays a critical role in gastrointestinal (GI) motility and stomach emptying. Here, we wanted to demonstrate the protective effects of supplemental 17ß-estradiol (E2) on NO-mediated gastric function. We showed E2 supplementation to alleviate oxidative and inflammatory stress in streptozotocin (STZ)-induced diabetic female mice. Our findings suggest that daily administration of E2 at therapeutic doses is beneficial for metabolic homeostasis. This restoration occurs via regulating and modulating the expression/function of glycogen synthase kinase-3ß (GSK-3ß), nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), Phase II enzymes, MAPK- and nuclear factor kappa-light-chain-enhancer of activated B cells (NFkB)-mediated inflammatory cytokines (IL-1ß, IL-6, TNFα, IGF-1), and gastric apoptotic regulators. We also showed E2 supplementation to elevate GCH-1 protein levels in female diabetic mice. Since GCH-1 facilitates the production of tetrahydrobiopterin (BH4, cofactor for nNOS), an increase in GCH-1 protein levels in diabetic mice may improve their GE and nitrergic function. Our findings provide new insights into the impact of estrogen on gastric oxidative stress and intracellular inflammatory cascades in the context of Gp.

Saliva as a diagnostic tool to measure polycyclic aromatic hydrocarbon exposure in dental patients exposed to intimate partner violence (IPV).

BACKGROUND: Social habits such as tobacco use, alcohol consumption, and chemically contaminated diet contribute to poor oral health. Intimate Partner Violence (IPV) is a global public health epidemic which can exacerbate the prevalence of health conditions affecting a victim's lifespan. This study investigates using saliva as a biomarker for detecting levels of benzo(a)pyrene [B(a)P]; a toxicant present in cigarette smoke and barbecued meat in a population of IPV + female patients. METHODS: A cross-sectional IRB-approved study utilized 63 female participants (37 African Americans [AA], and 26 non-African Americans [NAA]), who provided consent for the study. Participants submitted samples of saliva, as well as questionnaires about demographics, health history, and a well-validated (IPV) screen. RESULTS: The prevalence of IPV was greater in AA compared to NAA. While the concentrations of PAHs/B(a)P detected in saliva of IPV samples in NAA were generally within the range of B(a)P reported for saliva from elsewhere, the concentrations were high in some IPV positive samples. Among the B(a)P metabolites, the concentrations of B(a)P 7,8-diol, B(a)P 3,6- and 6,12-dione metabolites were greater than the other metabolite in both AA and non-AA groups who were positive. CONCLUSION: Our study supports the use of saliva as a potential "diagnostic rheostat" to identify toxicants that may exacerbate/precipitate systemic disease in female victims of IPV. In addition, our study is the first to report that IPV may precipitate the accumulation of B(a)P in oral cavity that can alter inflammatory cascades and increase risk of poor health outcomes in this population of patients.

Interleukin-17A is associated with flow-mediated dilation and interleukin-4 with carotid plaque in persons with HIV.

OBJECTIVE: Chronic inflammation contributes to the high burden of cardiovascular disease (CVD) in persons with HIV (PWH). HIV has broad effects on innate and adaptive immune cells, including innate lymphoid cells (ILCs) and CD4+ T-helper cells. At present, the relationship between CVD and plasma cytokines reflecting ILC/T-helper responses in PWH is not well defined. We investigated relationships between plasma cytokines and subclinical atherosclerosis. DESIGN: A cross-sectional study. METHODS: We recruited 70 PWH on a single antiretroviral regimen (efavirenz, teno- fovir, and emtricitabine) with at least 12 months of suppressed viremia and 30 HIVnegative controls. We quantified plasma cytokines and chemokines, including inter- feron-g, interleukin (IL)-4, IL-13, and IL-17A, markers of macrophage activation, and markers of endothelial activation using multiplex assays and ELISA. Cytokines were grouped using Ward's hierarchical clustering. Brachial artery flow-mediated dilation (FMD) and carotid plaque burden were determined using ultrasound. Multivariable linear regression and negative binomial regression analyses were used to assess the relationships of plasma biomarkers and endpoints adjusted for CVD risk factors. RESULTS: We identified three distinct clusters in PWH, one containing Th1/Th2/ILC1/ ILC2 type cytokines, one with Th17/ILC3/macrophage-related cytokines, and a less specific third cluster. Lower FMD was associated with higher plasma IL-17A and macrophage inflammatory protein-1 a. In contrast, IL-4, a Th2/ILC2 type cytokine, was associated with carotid plaque. When HIV-negative controls were added to the models clustering was more diffuse, and these associations were attenuated or absent. CONCLUSION: Th17/ILC3 and Th2/ILC2-mediated immune mechanisms may have distinct roles in endothelial dysfunction and atherosclerotic plaque formation, respectively, in PWH.

Nrf2 attenuates hyperglycemia-induced nNOS impairment in adult mouse primary enteric neuronal crest cells and normalizes stomach function.

Enteric neuronal cells play a vital role in gut motility in humans and experimental rodent models. Patients with diabetes are more vulnerable to gastrointestinal dysfunction due to enteric neuronal degeneration. In this study, we examined the mechanistic role and regulation of nuclear factor-erythroid 2-related factor 2 (Nrf2) in hyperglycemia-induced enteric neuronal cell apoptosis in vitro by using adult mouse primary enteric neuronal crest cells (pENCs). Our data show that hyperglycemia (HG) or inhibition of Nrf2 induces apoptosis by elevating proinflammatory cytokines, reactive oxygen species (ROS) and suppresses neuronal nitric oxide synthase (nNOS-α) via PI3K/Nrf2-mediated signaling. Conversely, treating pENCs with cinnamaldehyde (CNM), a naturally occurring Nrf2 activator, prevented HG-induced apoptosis. These novel data reveal a negative feedback mechanism for GSK-3 activation. To further demonstrate that loss of Nrf2 leads to inflammation, oxidative stress, and reduces nNOS-mediated gastric function, we have used streptozotocin (STZ)-induced diabetic and Nrf2 null female mice. In vivo activation of Nrf2 with CNM (50 mg/kg, 3 days a week, ip) attenuated impaired nitrergic relaxation and delayed gastric emptying (GE) in conventional type 1 diabetic but not in Nrf2 null female mice. Supplementation of CNM normalized diabetes-induced altered gastric antrum protein expression of 1) p-AKT/p-p38MAPK/p-GSK-3ß, 2) BH4 (cofactor of nNOS) biosynthesis enzyme GCH-1, 3) nNOSα, 4) TLR4, NF-κB, and 5) inflammatory cytokines (TNF-α, IL-1ß, IL-6). We conclude that activation of Nrf2 prevents hyperglycemia-induced apoptosis in pENCs and restores nitrergic-mediated gastric motility and GE in STZ-induced diabetes female mice.NEW & NOTEWORTHY Primary neuronal cell crust (pENCs) in the intestine habitats nNOS and Nrf2, which was suppressed in diabetic gastroparesis. Activation of Nrf2 restored nNOS by suppressing inflammatory markers in pENCs cells. Inhibition of Nrf2 reveals a negative feedback mechanism for the activation of GSK-3. Activation of Nrf2 alleviates STZ-induced delayed gastric emptying and nitrergic relaxation in female mice. Activation of Nrf2 restored impaired gastric BH4 biosynthesis enzyme GCH-1, nNOSα expression thus regulating nitric oxide levels.

Mechanistic role of antioxidants in rescuing delayed gastric emptying in high fat diet induced diabetic female mice.

Diabetic gastroparesis (DG) exhibits delayed gastric emptying (GE) due to impaired gastric non-adrenergic, non-cholinergic (NANC) relaxation. These defects are due to loss or reduction of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) that causes reduced expression and/or dimerization of neuronal nitric oxide synthase alpha (nNOSα) gene expression and function. We investigated the effect of potent Nrf2 activators (cinnamaldehyde [CNM] & curcumin [CUR]) on GE in obesity-induced diabetic female mice. We fed adult female homozygous Nfe2l2-/- (Nrf2 KO) and wild-type (WT) female mice with either a high-fat diet (HFD) or a normal diet (ND) for a period of 16 weeks. Groups of HFD mice were fed with CUR or CNM either at 6th or 10th week respectively. Our results demonstrate that supplementation of CNM or CUR restored impaired nitrergic relaxation and attenuated delayed GE in HFD fed mice. Supplementation of CNM or CUR normalized altered gastric antrum protein expression of (1) p-ERK/p-JNK/MAPK/p-GSK-3ß, (2) BH4 (Cofactor of nNOS) biosynthesis enzyme GCH-1 and the GSH/GSSG ratio, (3) nNOSα protein & dimerization and soluble guanylate cyclase (sGC), (4) AhR and ER expression, (5) inflammatory cytokines (TNF α, IL-1ß, IL-6), (6)TLR-4, as well as (7) reduced oxidative stress markers in WT but not in Nrf2 KO obesity-induced chronic diabetic female mice. Immunoprecipitation experiments revealed an interaction between nNOS and Nrf2 proteins. Our results conclude that Nrf2 activation restores nitrergic-mediated gastric motility and GE by normalizing inflammation and oxidative stress induced by obesity-induced chronic diabetes.

COVID-19 and Cancer Comorbidity: Therapeutic Opportunities and Challenges.

The coronavirus disease 2019 (COVID-19) is a viral disease caused by a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that affects the respiratory system of infected individuals. COVID-19 spreads between humans through respiratory droplets produced when an infected person coughs or sneezes. The COVID-19 outbreak originated in Wuhan, China at the end of 2019. As of 29 Sept 2020, over 235 countries, areas or territories across the globe reported a total of 33,441,919 confirmed cases, and 1,003,497 confirmed deaths due to COVID-19. Individuals of all ages are at risk for infection, but in most cases disease severity is associated with age and pre-existing diseases that compromise immunity, like cancer. Numerous reports suggest that people with cancer can be at higher risk of severe illness and related deaths from COVID-19. Therefore, managing cancer care under this pandemic is challenging and requires a collaborative multidisciplinary approach for optimal care of cancer patients in hospital settings. In this comprehensive review, we discuss the impact of the COVID-19 pandemic on cancer patients, their care, and treatment. Further, this review covers the SARS-CoV-2 pandemic, genome characterization, COVID-19 pathophysiology, and associated signaling pathways in cancer, and the choice of anticancer agents as repurposed drugs for treating COVID-19.

SARS-CoV-2 Infection and Oral Health: Therapeutic Opportunities and Challenges.

The novel corona virus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), and the disease it causes, COVID-19 (Coronavirus Disease-2019) have had multi-faceted effects on a number of lives on a global scale both directly and indirectly. A growing body of evidence suggest that COVID-19 patients experience several oral health problems such as dry mouth, mucosal blistering, mouth rash, lip necrosis, and loss of taste and smell. Periodontal disease (PD), a severe inflammatory gum disease, may worsen the symptoms associated with COVID-19. Routine dental and periodontal treatment may help decrease the symptoms of COVID-19. PD is more prevalent among patients experiencing metabolic diseases such as obesity, diabetes mellitus and cardiovascular risk. Studies have shown that these patients are highly susceptible for SARS-CoV-2 infection. Pro-inflammatory cytokines and oxidative stress known to contribute to the development of PD and other metabolic diseases are highly elevated among COVID-19 patients. Periodontal health may help to determine the severity of COVID-19 infection. Accumulating evidence shows that African-Americans (AAs) and vulnerable populations are disproportionately susceptible to PD, metabolic diseases and COVID-19 compared to other ethnicities in the United States. Dentistry and dental healthcare professionals are particularly susceptible to this virus due to the transferability via the oral cavity and the use of aerosol creating instruments that are ubiquitous in this field. In this review, we attempt to provide a comprehensive and updated source of information about SARS-CoV-2/COVID-19 and the various effects it has had on the dental profession and patients visits to dental clinics. Finally, this review is a valuable resource for the management of oral hygiene and reduction of the severity of infection.

Porphyromonas gingivalis infection alters Nrf2-phase II enzymes and nitric oxide in primary human aortic endothelial cells.

BACKGROUND: Periodontal disease (PD) is known to be associated with endothelial dysfunction in patients with coronary artery and/or cardiovascular disease. In our study, we sought to explore the virulence of P. gingivalis (Pg) affecting glycogen synthase kinase 3 beta (GSK-3ß)/nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/tetrahydrobiopterin (BH4 )/ nitric oxide synthase (NOS) expression in primary human aortic endothelial cells (pHAECs). METHODS: pHAECs were infected for 48 hours with Pg in vitro using the Human oxygen-Bacteria anaerobic coculture technique. Cell viability was determined, and target gene expression changes were evaluated by quantitative real-time polymerase chain reaction at the end of each incubation period. RESULTS: Pg impaired pHAEC viability 24 hours post-infection. Pg infection reduced mRNA expression levels of endothelial NOS (eNOS), Nrf2, and Phase II enzymes (heme oxygenase-1, catalase, superoxide dismutase-1) in a time-dependent manner. Significant (P <0.05) increase in the inflammatory markers (interleukin [IL]-1ß, IL-6, and tumor necrosis factor-α) were observed in the medium as well as in the infected cells. Interestingly, inducible NOS mRNA levels showed a significant (P <0.05) increase at 12 hours and 24 hours and were reduced at later time points. BH4 (cofactor of eNOS) biosynthesis enzyme dihydrofolate reductase (DHFR, salvage pathway) mRNA levels showed a significant (P <0.05) decrease, while mRNA levels of GSK-3ß were elevated. CONCLUSIONS: These results suggest that periodontal bacterial infection may cause significant changes in the endothelial GSK-3ß/BH4 /eNOS/Nrf2 pathways, which may lead to impaired vascular relaxation. Greater understanding of the factors that adversely affect endothelial cell function could contribute to the development of new therapeutic compounds to treat PD-induced vascular diseases.

Role of sex hormones and their receptors on gastric Nrf2 and neuronal nitric oxide synthase function in an experimental hyperglycemia model.

BACKGROUND: Gastroparesis, a condition of abnormal gastric emptying, is most commonly observed in diabetic women. To date, the role of ovarian hormones and/or gastric hormone receptors on regulating nitrergic-mediated gastric motility remains inconclusive. AIM: The purpose of this study is to investigate whether sex hormones/their receptors can attenuate altered Nuclear factor (erythroid-derived 2)-like 2 (Nrf2), neuronal Nitric Oxide Synthase (nNOS) expression and nitrergic relaxation in gastric neuromuscular tissues exposed to in-vitro hyperglycemia (HG). METHODS: Gastric neuromuscular sections from adult female C57BL/6 J mice were incubated in normoglycemic (NG, 5 mM) or hyperglycemic (30 mM or 50 mM) conditions in the presence or absence of selective estrogen receptor (ER) agonists (ERα /PPT or ERß: DPN); or non-selective sex hormone receptor antagonists (ER/ICI 182,780, or progesterone receptor (PR)/ RU486) for 48 h. mRNA, protein expression and nitrergic relaxation of circular gastric neuromuscular strips were assessed. RESULTS: Our findings in HG, compared to NG, demonstrate a significant reduction in ER, Nrf2, and nNOS expression in gastric specimens. In addition, in-vitro treatment with sex hormones and/or their agonists significantly (*p < 0.05) restored Nrf2/nNOSα expression and total nitrite production. Conversely, ER, but not PR, antagonist significantly reduced Nrf2/nNOSα expression and nitrergic relaxation. CONCLUSIONS: Our data suggest that ER's can regulate nitrergic function by improving Nrf2/nNOS expression in experimental hyperglycemia.

Inhibition of GSK-3ß restores delayed gastric emptying in obesity-induced diabetic female mice.

Diabetic gastroparesis (DG) is a clinical syndrome characterized by delayed gastric emptying (DGE). Loss of nuclear factor erythroid 2-related factor 2 (Nrf2) is associated with reduced neuronal nitric oxide synthase-α (nNOSα)-mediated gastric motility and DGE. Previous studies have shown that nuclear exclusion and inactivation of Nrf2 is partly regulated by glycogen synthase kinase 3ß (GSK-3ß). In the current study, the molecular signaling of GSK-3ß-mediated Nrf2 activation and its mechanistic role on DG were investigated in high-fat diet (HFD)-induced obese/Type 2 diabetes (T2D) female mice. Adult female C57BL/6J mice were fed with HFD or normal diet (ND) with or without GSK-3ß inhibitor (SB 216763, 10 mg/kg body wt ip) start from the 14th wk and continued feeding mice for an additional 3-wk time period. Our results show that treatment with GSK-3ß inhibitor SB attenuated DGE in obese/T2D mice. Treatment with SB restored impaired gastric 1) Nrf2 and phase II antioxidant enzymes through PI3K/ERK/AKT-mediated pathway, 2) tetrahydrobiopterin (BH4, cofactor of nNOS) biosynthesis enzyme dihydrofolate reductase, and 3) nNOSα dimerization in obese/T2 diabetic female mice. SB treatment normalized caspase 3 activity and downstream GSK-3ß signaling in the gastric tissues of the obese/T2 diabetic female mice. In addition, GSK-3ß inhibitor restored impaired nitrergic relaxation in hyperglycemic conditions. Finally, SB treatment reduced GSK3 marker, pTau in adult primary enteric neuronal cells. These findings emphasize the importance of GSK-3ß on regulating gastric Nrf2 and nitrergic mediated gastric emptying in obese/diabetic rodents.NEW & NOTEWORTHY Inhibition of glycogen synthase kinase 3ß (GSK-3ß) with SB 216763 attenuates delayed gastric emptying through gastric nuclear factor erythroid 2-related factor 2 (Nrf2)-phase II enzymes in high-fat diet-fed female mice. SB 216763 restored impaired gastric PI3K/AKT/ ß-catenin/caspase 3 expression. Inhibition of GSK-3ß normalized gastric dihydrofolate reductase, neuronal nitric oxide synthase-α expression, dimerization and nitrergic relaxation. SB 216763 normalized both serum estrogen and nitrate levels in female obese/Type 2 diabetes mice. SB 216763 reduced downstream signaling of GSK-3ß in enteric neuronal cells in vitro.

Supplementation of 17ß-Estradiol Normalizes Rapid Gastric Emptying by Restoring Impaired Nrf2 and nNOS Function in Obesity-Induced Diabetic Ovariectomized Mice.

Gastroparesis (Gp) is a multifactorial condition commonly observed in females and is characterized by delayed or rapid gastric emptying (GE). The role of ovarian hormones on GE in the pathogenesis of obesity induced type 2 diabetes mellitus (T2DM) is completely unknown. The aims of our study are to investigate whether supplementation of 17ß-estradiol (E2) or progesterone (P4) restores impaired nuclear factor erythroid 2-related factor 2 (Nrf2, an oxidative stress-responsive transcription factor) and nitric oxide (NO)-mediated gastric motility in ovariectomized (OVX) mice consuming a high-fat diet (HFD, a model of T2DM). Groups of OVX+HFD mice were administered daily subcutaneous doses of either E2 or P4 for 12 weeks. The effects of E2 and P4 on body weight, metabolic homeostasis, solid GE, gastric antrum NO-mediated relaxation, total nitrite levels, neuronal nitric oxide synthase (nNOSα), and its cofactor expression levels were assessed in OVX+HFD mice. HFD exacerbated hyperglycemia and insulinemia while accelerating GE (p < 0.05) in OVX mice. Exogenous E2, but not P4, attenuated rapid gastric emptying and restored gastric nitrergic relaxation, total nitrite levels, nNOSα, and cofactor expression via normalizing Nrf2-Phase II enzymes, inflammatory response, and mitogen-activated protein kinase (MAPK) protein expression in OVX+HFD mice. We conclude that E2 is beneficial in normalizing metabolic homeostasis and gastric emptying in obese, diabetic OVX mice consuming a fat-rich diet.

Activation of Nrf2 attenuates delayed gastric emptying in obesity induced diabetic (T2DM) female mice.

Diabetic gastroparesis (GP) is a clinical syndrome characterized by delayed gastric emptying (DGE). Loss of Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) led to reduced nNOSα mediated gastric motility and DGE. The molecular signaling of cinnamaldehyde (CNM) mediated Nrf2 activation and its mechanistic role on DGE were further investigated in obese/T2D female mice. Adult female homozygous Nfe2l2-/- (C57BL/6J) and their wild-type (WT) littermates (Nfe2l2+/+) mice were fed with high fat diet (HFD; Obese/T2D model), or normal diet (ND) with or without CNM (50 mg/kg b.w; i.p). Supplementation of CNM attenuated (p < 0.05) DGE in WT female but not in Nrf2 KO Obese/T2D mice. CNM (1) normalized serum estradiol-17ß levels, (2) induced gastric Nrf2 and phase II antioxidant enzymes through extracellular signal-regulated kinase, (ERK)/c-Jun N-terminal kinase (JNK)/p38 mitogen-activated protein kinase (MAPK), (3) reduced glucose synthase kinase 3 beta (GSK3ß) and aryl hydrocarbon receptor (AhR) and this was associated with (4) increased estrogen receptor expression, BH4 (Cofactor of nNOS) biosynthesis enzyme GCH-1 and nNOSα dimerization in WT Obese/T2 diabetic female mice. In addition, CNM restored impaired nitrergic relaxation in hyperglycemic conditions. These findings emphasize the importance of Nrf2 in maintaining nNOSα mediated GE and may have a translational relevance to treat obese/diabetic gastroparesis in women.

Sepiapterin alleviates impaired gastric nNOS function in spontaneous diabetic female rodents through NRF2 mRNA turnover and miRNA biogenesis pathway.

An impaired nitrergic system and altered redox signaling contribute to gastric dysmotility in diabetics. Our earlier studies show that NF-E2-related factor 2 (NRF2) and phase II antioxidant enzymes play a vital role in gastric neuronal nitric oxide synthase (nNOS) function. This study aims to investigate whether supplementation of sepiapterin (SEP), a precursor for tetrahydrobiopterin (BH4) (a cofactor of NOS) via the salvage pathway, restores altered nitrergic systems and redox balance in spontaneous diabetic (DB) female rats. Twelve-week spontaneous DB and age-matched, non-DB rats, with and without dietary SEP (daily 20 mg/kg body wt for 10 days) treatment, were used in this study. Gastric antrum muscular tissues were excised to investigate the effects of SEP in nitrergic relaxation and the nNOS-nitric oxide (NO)-NRF2 pathway(s). Dietary SEP supplementation significantly ( P < 0.05) reverted diabetes-induced changes in nNOS dimerization and function; nitric oxide (NO) downstream signaling molecules; HSP-90, a key regulator of nNOSα activity and dimerization; miRNA-28 that targets NRF2 messenger RNA (mRNA), and levels of microRNA (miRNA) biogenesis pathway components, such as DGCR8 (DiGeorge Syndrome Critical Region Gene 8) and TRBP (HIV1-1 transactivating response RNA-binding protein). These findings emphasize the importance of the BH4 pathway in regulating gastric motility functions in DB animals by modulating nNOSα dimerization in association with changes in enteric NRF2 and NO downstream signaling. Our results also identify a new pathway, wherein SEP regulates NRF2 mRNA turnover by suppressing elevated miRNA-28, which could be related to alterations in miRNA biogenesis pathway components. NEW & NOTEWORTHY This study is the first to show a causal link between NF-E2-related factor 2 (NRF2) and neuronal nitric oxide synthase (nNOS) in gastric motility function. Our data demonstrate that critical regulators of the miRNA biosynthetic pathway are upregulated in the diabetic (DB) setting; these regulators were rescued by sepiapterin (SEP) treatment. Finally, we show that low dihydrofolate reductase expression may lead to impaired nNOS dimerization/function-reduced nitric oxide downstream signaling and elevate oxidative stress by suppressing the NRF2/phase II pathway through miRNA; SEP treatment restored all of the above in DB gastric muscular tissue. We suggest that tetrahydrobiopterin supplementation may be a useful therapy for patients with diabetes, as well as women with idiopathic gastroparesis.

Role of oral and gut microbiome in nitric oxide-mediated colon motility.

Periodontal disease (PD), a severe form of gum disease, is among the most prevalent chronic infection in humans and is associated with complex microbial synergistic dysbiosis in the subgingival cavity. The immune system of the body interacts with the microbes as the plaque extends and propagates below the gingival sulcus. Once bacteria reach the gingival sulcus, it can enter the blood stream and affect various areas of the human body. The polymicrobial nature of periodontal disease, if left untreated, promotes chronic inflammation, not only within the oral cavity, but also throughout the human body. Alterations seen in the concentrations of healthy gut microbiota may lead to systemic alterations, such as gut motility disorders, high blood pressure, and atherosclerosis. Although gut microbiome has been shown to play a vital role in intestinal motility functions, the role of oral bacteria in this setting remains to be investigated. It is unclear whether oral microbial DNA is present in the large intestine and, if so, whether it alters the gut microbiome. In addition, polybacterial infection induced PD reduced nitric oxide (NO) synthesis and antioxidant enzymes in rodent colon. In this review, we will discuss the interactions between oral and gut microbiome, specifics of how the oral microbiome may modulate the activities of the gut microbiome, and possible ramifications of these alterations.

Identification of Specific Oral and Gut Pathogens in Full Thickness Colon of Colitis Patients: Implications for Colon Motility.

Impaired colon motility is one of the leading problems associated with inflammatory bowel disease (IBD). An expanding body of evidence supports the role of microbiome in normal gut function and in progression of IBD. The objective of this work is to determine whether diseased full thickness colon specimens, including the neuromuscular region (critical for colon motility function), contain specific oral and gut pathogens. In addition, we compared the differences in colon microbiome between Caucasians (CA) and African Americans (AA). Thirty-nine human full thickness colon (diseased colon and adjacent healthy colon) specimens were collected from Crohn's Colitis (CC) or Ulcerative Colitis (UC) patients while they underwent elective colon surgeries. We isolated and analyzed bacterial ribosomal RNA (rRNA) from colon specimens by amplicon sequencing of the 16S rRNA gene region. The microbiome proportions were quantified into Operational Taxonomic Units (OTUs) by analysis with Quantitative Insights Into Microbial ecology (QIIME) platform. Two hundred twenty-eight different bacterial species were identified by QIIME analysis. However, we could only decipher the species name of fifty-three bacteria. Our results show that proportion of non-detrimental bacteria in CC or UC colon samples were altered compared to adjacent healthy colon specimens. We further show, for the first time in full thickness colon specimens, that microbiome of CC and UC diseased specimens is dominated by putative oral pathogens belonging to the Phyla Firmicutes (Streptococcus, Staphylococcus, Peptostreptococcus), and Fusobacteria (Fusobacterium). In addition, we have identified patterns of differences in microbiome levels between CA and AA specimens with potential implications for health disparities research. Overall, our results suggest a significant association between oral and gut microbes in the modulation of colon motility in colitis patients.

Influence of Intimate Partner Violence (IPV) Exposure on Cardiovascular and Salivary Biosensors: Is There a Relationship?

BACKGROUND/PURPOSE: Intimate partner violence (IPV) is a global public health epidemic that initiates/exacerbates health consequences affecting a victim's lifespan. IPV can significantly predispose women to a lifetime risk of developing cardiovascular disease (CVD) due to the effects of stress and inflammation. This study investigates the correlation among IPV exposure, in-vivo CVD events, and inflammatory biomarkers as predictor indices(s) for CVD in female dental patients. METHODS: Of 37 women enrolled in this study, 19 were African-American (AA) and 18 non-African-American (non-AA) and their ages ranged from 19 to 63 years. IPV-exposure and stress-induced in-vivo CVD events such as Chest Pain (CP) and Heart palpitations were recorded from all enrolled subjects. Cardiovascular events were obtained through surveys by patient self-report. Saliva specimens were obtained from all women and were analyzed for CVD biomarkers using multiplex-ELISA. RESULTS: The prevalence of IPV was 51% (19/37) and statistically equivalent for AA and non-AA. The results show differences in experience of 1) CP (p < 0.01) and 2) heart palpitations (p < 0.02) when IPV + participants are compared with IPV- AA and non-AA cohorts. Of 10 CVD biomarkers analyzed, significant correlations between IPV+ and IPV- subjects were observed for biomarkers that include Interleukin-1ß/sCD40L; TNFα/sCD40L; Myoglobin/IL-1ß; CRP/sCD40L; CRP/IL-6; CRP/TNFα; TNFα/siCAM; CRP/MMP9; TNF-α/Adiponectin (p < 0.01). DISCUSSION/IMPLICATIONS: Analysis of in vivo CVD status showed that significant race/health disparities exist in IPV + cohorts, as well as increased expression of inflammatory mediators, specifically CRP, IL-1ß, IL-6, MMP9. Women who have experienced IPV may be a target cohort for primary prevention of CVD. The use of salivary biomarkers and our protocol may provide a less invasive method to help increase identification of victims at risk for IPV and CVD and potentially decrease other health injuries associated with IPV exposure.