A combination treatment of low-dose dexamethasone and aspirin-triggered resolvin D1 reduces Sjögren syndrome-like features in a mouse model.

Background: Sjögren syndrome (SS) is an autoimmune disease characterized by lymphocytic infiltration and diminished secretory function of the salivary glands. Dexamethasone (DEX) resolves dry mouth and lymphocytic infiltration; however, this treatment is difficult to maintain because of multiple adverse effects (eg, osteoporosis and skin thinning); likewise, aspirin-triggered resolvin D1 (AT-RvD1) increases saliva secretion but cannot eliminate lymphocytic infiltration. Previous studies showed that a combination of low-dose DEX with AT-RvD1 before disease onset prevents SS-like features in a mouse model; however, this is not clinically practical because there are no reliable indicators of SS before disease onset. Therefore, the authors applied the combined treatment at disease onset to show its efficacy and comparative lack of adverse effects, so that it may reasonably be maintained over a patient's lifetime. Methods: NOD/ShiLtJ mice were treated with ethanol (vehicle control), high-dose DEX alone, AT-RvD1 alone, or a combination of low-dose DEX with AT-RvD1 at disease onset for 8 weeks. Then saliva flow rates were measured, and submandibular glands were harvested for histologic analyses. Results: A combined treatment of low-dose DEX with AT-RvD1 significantly decreased mast cell degranulation and lymphocytic infiltration, increased saliva secretion, and restored apical aquaporin-5 expression in submandibular glands of NOD/ShiLtJ mice. Conclusions: Low-dose DEX combined with AT-RvD1 reduces the severity of SS-like manifestation and prevents the development of advanced and potentially irreversible damage, all in a form that can reasonably be administered indefinitely without the need to cease treatment because of secondary effects.

Neurologic involvement in seronegative primary Sjögren's syndrome with positive minor salivary gland biopsy: a single-center experience.

Objective: To assess the demographics, neurologic manifestations, comorbidities, and treatment of patients with seronegative primary Sjögren's syndrome (pSS). Patients and methods: We conducted a retrospective chart review on patients with seronegative pSS evaluated by a neurologist at the University of Utah Health between January 2010 and October 2018. The diagnosis was based on characteristic symptoms, positive minor salivary gland biopsy according to the American-European Consensus Group 2002 criteria, and seronegative antibody status. Results: Of 45 patients who met the study criteria, 42 (93.3%) were Caucasian, and 38 (84.4%) were female. The patients' mean age at diagnosis was 47.8 ± 12.6 (range 13-71) years. Paresthesia, numbness and dizziness, and headache were noted in 40 (88.9%), 39 (86.7%), and 36 patients (80.0%), respectively. Thirty-four patients underwent brain magnetic resonance imaging. Of these, 18 (52.9%) showed scattered nonspecific periventricular and subcortical cerebral white matter T2/fluid-attenuated inversion recovery hyperintense foci. Twenty-nine patients (64.4%) presented to the neurology clinic prior to pSS diagnosis, and the median delay in diagnosis from the first neurology clinic visit was 5 (interquartile ranges 2.0-20.5) months. Migraine and depression were the most common comorbidities in 31 patients (68.9%). Thirty-six patients received at least one immunotherapy, and 39 were on at least one medication for neuropathic pain. Conclusion: Patients often display various nonspecific neurological symptoms. Clinicians should express a high degree of skepticism regarding seronegative pSS and consider minor salivary gland biopsy to avoid delaying diagnosis, as undertreatment can affect patients' quality of life.

Specialized pro-resolving receptors are expressed in salivary glands with Sjögren's syndrome.

Our previous studies demonstrated that resolvin D1 (RvD1) and its aspirin-trigged (AT) form AT-RvD1, are effective in decreasing inflammation while restoring saliva flow rates in a Sjögren's syndrome (SS)-like mouse model before and after disease onset. Resolvins are specialized pro-resolving mediators (SPM) that actively regulate inflammation. However, we only have extensive data within the salivary glands for RvD1 and AT-RvD1, both of which bind to the receptor ALX/FPR2. As such, the presence of other SPM receptors is unknown within salivary glands. Therefore, the goal of this study was to determine the expression of SPM receptors in non-SS and SS patients. For this purpose, six human minor salivary glands from female subjects were analyzed by H&E using the Chisholm and Mason classification to determine the degree of lymphocytic infiltration. Next, confocal immunofluorescence analysis was performed to determine the presence and distribution of different SPM receptors in mucous acini and striated ducts. We observed diffuse presence of lymphocytic infiltration and clinical data were consistent with SS diagnosis in three patients. Moreover, confocal immunofluorescence analysis indicated the presence of the receptors ALX/FPR2, BLT1 and CMKLR1 in the mucous acini and striated ducts of both non-SS and SS patients. GPR32 was absent in SS and non-SS minor salivary glands. In summary, our results showed that various SPM receptors are expressed in non-SS and SS minor salivary glands, all of which may pose as potential targets for promoting pro-epithelial and anti-inflammatory/pro-resolution signaling on SS patients.

Laminin-1 Peptides Conjugated to Fibrin Hydrogels Promote Salivary Gland Regeneration in Irradiated Mouse Submandibular Glands.

Previous studies demonstrated that salivary gland morphogenesis and differentiation are enhanced by modification of fibrin hydrogels chemically conjugated to Laminin-1 peptides. Specifically, Laminin-1 peptides (A99: CGGALRGDN-amide and YIGSR: CGGADPGYIGSRGAA-amide) chemically conjugated to fibrin promoted formation of newly organized salivary epithelium both in vitro (e.g., using organoids) and in vivo (e.g., in a wounded mouse model). While these studies were successful, the model's usefulness for inducing regenerative patterns after radiation therapy remains unknown. Therefore, the goal of the current study was to determine whether transdermal injection with the Laminin-1 peptides A99 and YIGSR chemically conjugated to fibrin hydrogels promotes tissue regeneration in irradiated salivary glands. Results indicate that A99 and YIGSR chemically conjugated to fibrin hydrogels promote formation of functional salivary tissue when transdermally injected to irradiated salivary glands. In contrast, when left untreated, irradiated salivary glands display a loss in structure and functionality. Together, these studies indicate that fibrin hydrogel-based implantable scaffolds containing Laminin-1 peptides promote secretory function of irradiated salivary glands.

The use of BokaFlo™ instrument to measure salivary flow.

BACKGROUND: Dry mouth currently affects roughly 20% of the population and is a condition characterized by chronic hyposalivation and/or subjective reports of xerostomia. Low saliva flow can be indicative of other undiagnosed diseases, such as primary Sjogren's syndrome, and may contribute to difficulty chewing, increased caries susceptibility and infection. The passive drool test (PDT) is the primary method used to evaluate patients for hyposalivation but it is time-consuming and inconvenient. New methodology is needed to facilitate increased testing for hyposalivation in the dental clinic. The aim of this study was to evaluate an alternative method to measure salivary flow in dental offices. METHODS: In this study, we tested a new biomedical device, the BokaFlo™, to measure salivary flow in subjects in comparison to the current PDT standard. Participants completed an oral health questionnaire and saliva flow was evaluated by the PDT and the BokaFlo™ system. RESULTS: Saliva flow as measured by the BokaFlo™ positively correlated with the saliva flow measured by the PDT methodology (r = 0.22, p < 0.05). The device predicted low saliva flow in subjects with a sensitivity of 0.76 and specificity of 0.84 for subjects with hyposalivation, defined as a saliva flow rate of ≤ 0.1 ml/min. A significant negative correlation between the total oral health questionnaire score and the likelihood of participant exhibiting low salivary flow was observed (r = - 0.31, p < 0.006). CONCLUSION: The BokaFlo™ was effectively able to measure low saliva flow correlating with the PDT methodology and may provide more efficient testing of saliva flow in the dental office.

Comprehensive oral care improves treatment outcomes in male and female patients with high-severity and chronic substance use disorders.

BACKGROUND: Using data from a workforce training program funded by the Health Resources and Services Administration, the authors de-identified pre- and posttreatment assessments of high-severity and chronic substance use disorders (SUDs) to test the effect of integrated comprehensive oral health care for patients with SUDs on SUD therapeutic outcomes. METHODS: After 1 through 2 months of treatment at a SUD treatment facility, 158 male self-selected (First Step House) or 128 randomly selected sex-mixed (Odyssey House) patients aged 20 through 50 years with major dental needs received integrated comprehensive dental treatment. The SUD treatment outcomes for these groups were compared with those of matched 862 male or 142 sex-mixed patients, respectively, similarly treated for SUDs, but with no comprehensive oral health care (dental controls). Effects of age, primary drug of abuse, sex, and SUD treatment facility-influenced outcomes were determined with multivariate analyses. RESULTS: The dental treatment versus dental control significant outcomes were hazard ratio (95% confidence interval [CI]) 3.24 (2.35 to 4.46) increase for completion of SUD treatment, and odds ratios (95% CI) at discharge were 2.44 (1.66 to 3.59) increase for employment, 2.19 (1.44 to 3.33) increase in drug abstinence, and 0.27 (0.11 to 0.68) reduction in homelessness. Identified variables did not contribute to the outcomes. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Improvement in SUD treatment outcomes at discharge suggests that complementary comprehensive oral health care improves SUD therapeutic results in patients with SUDs. Integrated comprehensive oral health care of major dental problems significantly improves treatment outcomes in patients whose disorders are particularly difficult to manage, such as patients with SUDs.

Aspirin Triggered Resolvin D1 reduces inflammation and restores saliva secretion in a Sjögren's syndrome mouse model.

OBJECTIVES: SS is characterized by chronic inflammation of the salivary glands leading to loss of secretory function, thereby suggesting specialized pro-resolving mediators targeting inflammation to be a viable option for treating SS. Previous studies demonstrated that aspirin-triggered resolvin D1 (AT-RvD1) prevents chronic inflammation and enhances saliva secretion in a SS-like mouse model when applied before disease onset. However, this therapy cannot be used in SS patients given that diagnosis occurs post-disease onset and no reliable screening methods exist. Therefore, we examined whether treatment with AT-RvD1 reduces SS-like features in a mouse model post-disease onset. METHODS: Tail vein injections were performed in a SS-like mouse model both with and without AT-RvD1 post-disease onset for 8 weeks, with salivary gland function and inflammatory status subsequently determined. RESULTS: Treatment of a SS-like mouse model with AT-RvD1 post-disease onset restores saliva secretion in both females and males. Moreover, although AT-RvD1 treatment does not reduce the overall submandibular gland lymphocytic infiltration, it does reduce the number of T helper 17 cells within the infiltrates in both sexes. Finally, AT-RvD1 reduces SS-associated pro-inflammatory cytokine gene and protein expression levels in submandibular glands from female but not male mice. CONCLUSION: AT-RvD1 treatment administered post-disease onset reduces T helper 17 cells and successfully restores salivary gland function in a SS mouse model with variable effects noted by sex, thus warranting further examination of both the causes for the sex differences and the mechanisms responsible for the observed treatment effect.

Author Correction: AT-RvD1 Promotes Resolution of Inflammation in NOD/ShiLtJ mice.

A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Laminin-111-derived peptide conjugated fibrin hydrogel restores salivary gland function.

Hyposalivation reduces the patient quality of life, as saliva is important for maintaining oral health. Current treatments for hyposalivation are limited to medications such as the muscarinic receptor agonists, pilocarpine and cevimeline. However, these therapies only provide temporary relief. Therefore, alternative therapies are essential to restore salivary gland function. An option is to use bioengineered scaffolds to promote functional salivary gland regeneration. Previous studies demonstrated that the laminin-111 protein is critical for intact salivary gland cell cluster formation and organization. However, laminin-111 protein as a whole is not suitable for clinical applications as some protein domains may contribute to unwanted side effects such as degradation, tumorigenesis and immune responses. Conversely, the use of synthetic laminin-111 peptides makes it possible to minimize the immune reactivity or pathogen transfer. In addition, it is relatively simple and inexpensive as compared to animal-derived proteins. Therefore, the goal of this study was to demonstrate whether a 20 day treatment with laminin-111-derived peptide conjugated fibrin hydrogel promotes tissue regeneration in submandibular glands of a wound healing mouse model. In this study, laminin-111-derived peptide conjugated fibrin hydrogel significantly accelerated formation of salivary gland tissue. The regenerated gland tissues displayed not only structural but also functional restoration.

AT-RvD1 Promotes Resolution of Inflammation in NOD/ShiLtJ mice.

Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disease characterized by diminished secretory function of the exocrine glands. Treatments for hyposalivation are limited to the use of saliva substitutes and medications that provide only temporary relief. In light of the high degree of need and the limitations of current therapies, development of alternative treatments to restore functioning is essential. Resolvins (Rv), which are highly potent lipid mediators, offer a viable alternative for better treating inflammatory diseases such as SS. The goal of this study was to determine whether systemic preventive treatment with Aspirin-triggered RvD1 (AT-RvD1) reduces inflammation and preserves secretory functioning in NOD/ShiLtJ SS-like mice. Our results indicate that systemic treatment with AT-RvD1 diminishes the progression of the disease in salivary epithelium from female mice as follows: (a) improves secretory function, (b) reduces pro-inflammatory molecule gene expression, (c) increases anti-inflammatory molecule gene expression and (d) induces M2 macrophage polarization. Finally, AT-RvD1 decreases lymphocytic infiltration into the salivary glands when used with small doses of the steroid, dexamethasone, and promotes the tissue healing process.

Post-Irradiated Human Submandibular Glands Display High Collagen Deposition, Disorganized Cell Junctions, and an Increased Number of Adipocytes.

Salivary glands are vital for maintaining oral health. Head and neck radiation therapy is one of the most common causes of salivary gland hypofunction. Little is known about the structural changes that occur in salivary glands after radiation therapy. The aim of this study is to understand the structural changes that occur in post-irradiated human (submandibular gland [SMG]) as compared with untreated ones. We determined changes in epithelial polarity, presence of collagen deposition, and alteration in adipose tissue. We used formalin-fixed paraffin-embedded human SMG from two female subjects exposed to head and neck irradiation. We utilized hematoxylin and eosin staining and Masson's Trichrome staining. The immunostained tissue sections were examined using confocal microscopy. The number and size of adipocytes per tissue section were calculated using ImageJ, Prism, and SPSS software. Post-irradiated human SMG displayed high collagen deposition, disorganized cell junctions, and an increased number of adipocytes as compared with non-irradiated controls. These findings are important to improve our understanding of the individual risk and variation in radiation-related salivary gland dysfunction.

Aspirin-Triggered Resolvin D1 Versus Dexamethasone in the Treatment of Sjögren's Syndrome-Like NOD/ShiLtJ Mice - A Pilot Study.

Resolvin D1 (RvD1) and its aspirin-triggered epimeric form (AT-RvD1) are endogenous lipid mediators (derived from docosahexaenoic acid, DHA) that control the duration and magnitude of inflammation in models of complex diseases. Our previous studies demonstrated that RvD1-mediated signaling pathways are expressed and active in salivary glands from rodents and humans. Furthermore, treatment of salivary cells with RvD1 blocked TNF-α-mediated inflammatory signals and improved epithelial integrity. The purpose of this pilot study was to determine the feasibility of treatment with AT-RvD1 versus dexamethasone (DEX) on inflammation (i.e., lymphocytic infiltration, cytokine expression and apoptosis) observed in submandibular glands (SMG) from the NOD/ShiLtJ Sjögren's syndrome (SS) mouse model before experimenting with a larger population. NOD/ShiLtJ mice were treated intravenously with NaCl (0.9%, negative control), AT-RvD1 (0.01-0.1 mg/kg) or DEX (4.125-8.25 mg/kg) twice a week for 14 weeks beginning at 4 weeks of age. At 18 weeks of age, SMG were collected for pathological analysis and detection of SS-associated inflammatory genes. The AT-RvD1 treatment alone did not affect lymphocytic infiltration seen in NOD/ShiLtJ mice while DEX partially prevented lymphocytic infiltration. Interestingly, both AT-RvD1 and DEX caused downregulation of SS-associated inflammatory genes and reduction of apoptosis. Results from this pilot study suggest that a systemic treatment with AT-RvD1 and DEX alone attenuated inflammatory responses observed in the NOD/ShiLtJ mice; therefore, they may be considered as potential therapeutic tools in treating SS patients when used alone or in combination.