Characterizing the Robustness of Distinct Clinical Assessments in Identifying Dry Eye Condition of Animal Models.

PURPOSE: The study aims to characterize the robustness of distinct clinical assessments in identifying the underlying conditions of dry eye disease (DED), with a specific emphasis on the involvement of conjunctival goblet cells. METHODS: Seven rabbits receiving surgical removal of the lacrimal and Harderian glands were divided into two groups, one with ablation of conjunctival goblet cells by topical soaking of trichloroacetic acid (TCA) to the bulbar conjunctiva (n = 3) and one without (n = 4), and the conditions of DED were assessed weekly using Schirmer test, tear breakup time (TBUT), tear osmolarity, and National Eye Institute (NEI) fluorescein staining grading. After 8 weeks, the rabbits were sacrificed, and the eyes were enucleated for histopathological examination. RESULTS: Histopathological analysis revealed corneal epithelial thinning in both groups. While TCA soaking significantly decreased the density of conjunctival goblet cells, DED rabbits without TCA also showed a partial reduction in goblet cell density, potentially attributable to dacryoadenectomy. Both groups showed significant decreases in Schirmer test and TBUT, as well as an increase in tear osmolarity. In DED rabbits with TCA soaking, tear osmolarity increased markedly, suggesting that tear osmolarity is highly sensitive to loss and/or dysfunction of conjunctival goblet cells. Fluorescein staining was gradually and similarly increased in both groups, suggesting that fluorescein staining may not reveal an early disruption of the tear film until the prolonged progression of DED. CONCLUSION: The Schirmer test, TBUT, tear osmolarity, and NEI fluorescein grading are distinct, yet complementary, clinical assessments for the evaluation of DED. By performing these assessments in definitive DED rabbit models, both with and without ablation of conjunctival goblet cells, the role of these cells in the homeostasis of tear osmolarity is highlighted. Characterizing the robustness of these assessments in identifying the underlying conditions of DED will guide a more appropriate management for patients with DED.

Hyperprolactinemia modifies extracellular matrix components associated with collagen fibrillogenesis in harderian glands of non- and pregnant female mice.

The harderian gland (HG) is a gland located at the base of the nictating membrane and fills the inferomedial aspect of the orbit in rodents. It is under the influence of the hypothalamic-pituitary-gonadal axis and, because of its hormone receptors, it is a target tissue for prolactin (PRL) and sex steroid hormones (estrogen and progesterone). In humans and murine, the anterior surface of the eyes is protected by a tear film synthesized by glands associated with the eye. In order to understand the endocrine changes caused by hyperprolactinemia in the glands responsible for the formation of the tear film, we used an animal model with metoclopramide-induced hyperprolactinemia (HPRL). Given the evidences that HPRL can lead to a process of cell death and tissue fibrosis, the protein expression of small leucine-rich proteoglycans (SLRPs) was analyzed through immunohistochemistry in the HG of the non- and the pregnant female mice with hyperprolactinemia. The SRLPs are related to collagen fibrillogenesis and they participate in pro-apoptotic signals. Our data revealed that high prolactin levels and changes in steroid hormones (estrogen and progesterone) can lead to an alteration in the amount of collagen, and in the structure of type I and III collagen fibers through changes in the amounts of lumican and decorin, which are responsible for collagen fibrillogenesis. This fact can lead to the impaired functioning of the HG by excessive apoptosis in the HG of the non- and the pregnant female mice with HPRL and especially in the HG of pregnancy-associated hyperprolactinemia.

Morphological and molecular changes in the Harderian gland of streptozotocin-induced diabetic rats.

Using a rat model of type 1 diabetes (T1D) obtained by treatment with streptozotocin, an antibiotic that destroys pancreatic ß-cells, we evaluated the influence of subsequent hyperglycemia on the morphology and physiology of the Harderian gland (HG). HG is located in the medial corner of the orbit of many terrestrial vertebrates and, in rodents, is characterized by the presence of porphyrins, which being involved in the phototransduction, through photo-oxidation, produce reactive oxygen species activating the autophagy pathway. The study focused on the expression of some morphological markers involved in cell junction formation (occludin, connexin-43, and α-tubulin) and mast cell number (MCN), as well as autophagic and apoptotic pathways. The expression of enzymes involved in steroidogenesis [steroidogenic acute regulatory protein (StAR), and 3ß-hydroxysteroid dehydrogenase (3ß-HSD)] and the level of lipid peroxidation by thiobarbituric acid reactive species assay were also evaluated. The results strongly indicate, for the first time, that T1D has a negative impact on the pathophysiology of rat HG, as evidenced by increased oxidative stress, morphological and biochemical alterations, hyperproduction and secretion of porphyrins, increased MCN, reduced protein levels of StAR and 3ß-HSD, and, finally, induced autophagy and apoptosis. All the combined data support the use of the rat HG as a suitable experimental model to elucidate the molecular damage/survival pathways elicited by stress conditions.

Morphological and functional relationship between the orbital gland and olfaction in Upupa epops (hoopoe) and Bubulcus ibis (cattle egret).

This study used both anatomical and histological techniques to investigate the orbital gland's topographic relationship with the surrounding system, using the hoopoe and cattle egret as biological models. Hoopoe has a spindle-shaped lacrimal gland that is suspended on the lateral edge of the frontal bone, whereas cattle egret has a tiny lacrimal gland that is embedded posteriorly within the periorbital fascia. The hoopoe's lacrimal gland has a single duct that runs parallel to the nasolacrimal duct and opens into the posterior nostril hole. In the cattle egret, the tubule-alveolar secretory components comprise neutral and acid glycosaminoglycan. In addition, the Harderian gland is found in both these species, but their draining ducts differ; the Harderian gland of the hoopoe opens into the anterodorsal to the conjunctival fornix, whereas the Harderian gland of the egret opens anteriorly. In both hoopoe and egret, the secretions of Harderian gland include neutral and acid glycosaminoglycan. The Harderian gland is categorized as type II in hoopoe and type I in cattle egrets. The present results concluded that both orbital glands of two bird species studied play an essential role in eye health, where cleaning and lubrication of the cornea surface. Furthermore, the lacrimal gland's location and secretory features may strengthen the olfactory sensitivity of hoopoe, which relies heavily on scent to locate their food, whereas egret relies heavily on visual cues.

High-fat diet affects autophagy and mitochondrial compartment in rat Harderian gland.

The Harderian gland (HG) of Rattus norvegicus is an orbital gland secreting lipids that accumulate in excess under condition of increased lipid metabolism. To study the response elicitated by lipid overload in rat HG, we housed the animals in thermoneutral conditions (28-30°C) in association to high fat diet (HFD). In HFD rats alterated blood lipid levels result in lipid accumulation in HG as demonstrated by the increased gland weight and histochemical/ultrastructural analyses. The HFD-caused oxidative stress forces the gland to trigger antioxidant defense mechanisms and autophagic process, such as lipophagy and mitophagy. Induction of mitochondrial DNA (mtDNA) damage and repair was stronger in HFD-rat HGs. An increase in marker expression levels of mitochondrial biogenesis, fission, and fusion occurred to counteract mtDNA copy number reduction and mitophagy. Therefore, the results demonstrate that rat HG activates autophagy as survival strategy under conditions of increased lipid metabolism and suggest a key role for mitophagy and membrane dynamics in the mitochondrial adaptive response to HFD.

Preliminary study of the ameliorative effects of melatonin on cadmium-induced morphological and biochemical alterations in the rat Harderian gland.

Herein is reported, for the first time in the rat Harderian gland (HG), the counteractive action of melatonin (Mlt), a well-known antioxidant radical scavenger, on the increased oxidative stress damages induced by a pro-oxidant substance, cadmium (Cd), an environmental pollutant also considered as endocrine disruptor. HG, an infraorbital gland present in almost all terrestrial vertebrates, produces a lipid secretion to lubricate the eyeball, as well as porphyrin/Mlt as light transducers. Moreover, HG is an extra-gonadal source of steroid sex hormones. Via ex vivo experiments lasting for 24 h, we verified the increased lipid peroxidation in Cd-treated glands, producing morphological alteration of the glandular epithelium, as well as an increased porphyrins accumulation. Moreover, Cd also induced a decreased protein level of the steroidogenic enzymes steroidogenic acute regulatory (StAR) and 3ßHSD, and an increased mast cell number. Results obtained with Mlt cotreatment demonstrated that it decreased the levels of Cd-induced oxidative damage, with reversal of all the observed modification. Furthermore, the TUNEL assay showed that the increased number of apoptotic cells in Cd-treated HG was counteracted by the contemporaneous Mlt administration. Results confirmed that Mlt treatment restored the levels of two autophagy markers, LC3 and p62, counteracting the autophagy Cd-induced. Interestingly, the positive effects of Mlt alone were highlighted by the decreased rate of lipid peroxidation as compared with the control, confirming its antioxidant action. Combined data further confirmed the antioxidant action of Mlt in counteracting the degeneration provoked by reactive oxygen species (ROS) in the rat HG, a tissue extremely susceptible to oxidative stress condition.

Dry eye symptoms in interferon regulatory factor 3-deficient mice due to herpes simplex virus infection in harderian gland and lacrimal gland.

PURPOSE: Dry eye syndrome (DES) is a multifactorial ocular disorder. The possible pathogens and pathogenic mechanisms for virus-related dry eye disease are largely unknown. The current study aimed to provide evidence for mechanisms contributing to DES induced by herpes simplex virus (HSV) infection in the harderian gland (HG) and lacrimal gland (LG). METHODS: We recorded the dry eye-like cornea pathology of irf3-/- mice infected with HSV-1 till 8 months of age. The slit-lamp and confocal microscopy was used to observe the corneal defects. TUNEL was used to detect the corneal apoptosis. Human corneas suffered from herpes stromal keratitis (HSK) were also analyzed as a comparison. Then, we measure the aqueous tear production with a phenol red thread test in irf3-/-mice, and recorded their tear film breakup time. HGs and LGs were sectioned and analyzed using HE and oil-red-O staining. For molecular signaling pathway analysis, we used mRNA sequencing to explore the related gene ontology. Western blotting (WB) and real-time reverse transcription-quantitative polymerase chain reaction were used to verify the level of the Akt signaling pathway and related inflammatory factors. RESULTS: Inoculated irf3-/- mice tended to develop dry eye-like symptoms, such as corneal keratinization, corneal cell apoptosis, and tear reduction. The HGs and LGs of irf3-/- mice showed increased level of HSV-1, and exhibited inflammatory pathological changes and impaired function, which explained the damaged tear film. WB and mRNA sequencing indicated that enhanced PI3K-Akt pathway in irf3-/- mice might account for the higher susceptibility to HSV infection. CONCLUSIONS: We observed evidence of DES in irf3-/- mice induced by HSV-1 infection in the HGs and LGs, which may introduce a potential novel target for DES treatment.

Infectious bronchitis virus infection in chicken: viral load and immune responses in Harderian gland, choanal cleft and turbinate tissues compared to trachea.

1. The role of the Harderian gland (HG), choanal cleft (CC) and turbinate in terms of IBV M41 viral load compared to the trachea, and immune (innate, cellular and mucosal) responses were studied in 21-day-old commercial broiler chickens.2. After virulent IBV M41 challenge, the antigen concentration detected either by quantitative RT-PCR or immunohistochemistry peaked at 2-3 days post challenge (dpc) in all tissues. Significant increases of lachrymal IBV-specific IgA and IgY levels were found at 4-5 dpc.3. Gene transcription showed a significant up-regulation of TLR3, MDA5, IL-6, IFN-α and IFN-ß, where patterns and magnitude fold-change of mRNA transcription were dependent on the gene and tissue type.4. The results demonstrated active IBV M41 replication in the HG, CC and turbinate, comparable to levels of replication found in the trachea. Data on immune-related genes in head-associated tissues provide further understanding on the immunobiology of IBV and offer opportunities to identify their use as quantitative biomarkers in pathogenicity and vaccination-challenge studies.

Hamster DAX1: Molecular insights, specific expression, and its role in the Harderian gland.

DAX1 plays an essential role in the differentiation and physiology of the Hypothalamic-Pituitary-Adrenal-Gonadal (HPAG) axis during embryogenesis. However, in adult tissues, in addition to the HPAG axis, evidence has not been found for its differential expression and function. We isolated the DAX1 cDNA to analyze its tissue localization and gene expression profiles in male and female hamsters' Harderian glands (HGs), Mesocricetus auratus. The isolated cDNA clone contains 1848 base pairs (bp), and a 1428-bp open reading frame (ORF) encodes a 476 amino acid protein. Sequence alignments and the phylogenetic tree display a relevant percentage of similarity with human (66%), rat (81%), and mouse (84%) sequences. In adult tissues, the mRNA distribution demonstrated that DAX1 is present in testis, ovaries, and male and female HGs. The highest expression profiles were identified in the adrenal glands, where females exhibit higher mRNA levels than males. The sexually dimorphic expression of DAX1 in adrenals suggests that its presence could be associated with regulating, functioning, and maintaining this endocrine tissue. These findings indicate that the DAX1 gene is limitedly expressed in adult tissues. In the HGs, we demonstrate the absence of sexually dimorphic gene expression. Our results suggest that DAX1 might have an additional physiological function outside of the HPAG axis, specifically in the HG, which may be required for the regulation of intracrine steroidogenesis, secretion, and maintenance of exocrine tissue.

Veterinary Management of Harderian Gland Tumors in Cancer Rainbow (crainbow) HER2-Positive Mice.

A Cancer Rainbow mouse line that expresses 3 fluorescently labeled isoforms of the tumor-driver gene HER2 (HER2BOW) was developed recently for the study of tumorigenesis in the mammary gland. The expression of 1 of the 3 HER2 isoforms in HER2BOW mice is induced through the Cre/lox system. However, in addition to developing palpable mammary tumors, HER2BOW mice developed orbital tumors, specifically of the Harderian gland. Mice were euthanized, and histopathologic examination of the Harderian gland tumors was performed. Tumors were characterized by adenomatous hyperplasia to multinodular adenomas of the Harderian gland. Fluorescent imaging of the Harderian gland tissue confirmed the expression of HER2 in the tumors. Here we discuss monitoring and palliative approaches to allow attainment of humane experimental endpoints of mammary tumor growth in this mouse line. We describe a range of interventions, including close monitoring, topical palliative care, and surgical bilateral enucleation. Based on our data and previous reports in the literature, the overexpression of HER2 in Harderian gland tissue and subsequent tumor formation likely was driven by MMTV-Cre expression in the Harderian gland.

Novel Lipids of the Rabbit Harderian Gland Improve Tear Stability in an Animal Model of Dry Eye Disease.

Purpose: Instability of the tear film leads to evaporative dry eye disease (EDED), but the Harderian gland in some terrestrial vertebrates may produce novel lipids that stabilize the tear film and protect against dry eye. Here, the nonpolar lipids in the Harderian gland and tears of the rabbit but absent in human tears were identified and tested in preclinical studies to determine whether they could treat severe EDED. Methods: Lipids were identified primarily by atmospheric pressure chemical ionization mass spectrometry (MS) and fragmentation MS/MS. An identified lipid was synthesized and formulated as an emulsion and as a cyclodextrin (CD) clathrate. Following doses with test agents and controls, tear film breakup time (TBUT), tear production, corneal fluorescein staining, macrophage infiltration, and goblet cell survival were measured using standard tests at 0, 2 and 4 weeks in an animal model of EDED. Results: The lipid emulsion increased TBUT (P < 0.01) and tear production (P < 0.05), while it decreased corneal staining (P < 0.01) compared to controls. The lipid CD formulation increased TBUT (P < 0.05) and tear production (P < 0.05) but had no significant effect on the remaining test parameters. There were no differences in macrophage infiltration and conjunctival impression cytology scores between the formulations and their vehicle controls. Conclusions: Lipids in the rabbit Harderian gland and tears differ from those identified in human meibum and tears. These unique rabbit lipids may confer a protective effect against EDED and, as supplements to human tears, fulfill a similar role.

Imbalance between the cellular proliferation and death in harderian gland of female mice with hyperprolactinemia.

OBJECTIVE: To assess the impact of the metoclopramide-induced hyperprolactinemia in cellular death and proliferation in the harderian gland of female mice. METHODS: Twenty female mice were divided into two groups of 10 animals each and treated: 0.2 mL of saline solution (controls, Ctr) and 200 µg of metoclopramide (experimental, hyperprolactinemia), both for 50 consecutive days and at 12:00 a.m. On the 50th day, the female were euthanized, and the harderian glands were removed and processed for immunohistochemistry for detected ki67 and TUNEL method. Data were statistically analyzed by unpaired Student's t test (p<0.05). RESULTS: The harderian gland of the hyperprolactinemia group showed increase in the immunoexpression of Ki67 and TUNEL compared to the Ctr group (p<0.05), and there was no significant difference in the amount of porphyrin in the HPrl group compared to the Ctr group. CONCLUSION: The hyperprolactinemia led to increased cell death in the acini the harderian gland and cell proliferation in the stroma glandular, fact that suggesting a reduction process of cellular activity and fibrosis, which suggests impairment in the functioning of the lacrimal harderian.

Change on apoptosis, autophagy and mitochondria of the Harderian gland in Cricetulus barabensis during age.

Harderian gland (HG) plays an important role in the physiological adaptation to terrestrial life, however, the mechanisms underlying the changes in the structure and function of the HG during aging remain unclear. This study investigated autophagy and apoptosis in the HG of striped dwarf hamsters (Cricetulus barabensis) of different ages (sub-adult, adult and aged groups) in both males and females. The results showed that LC3II/LC3I and puncta of LC3 were significantly higher in adult and aged individuals than sub-adults, whereas P62 decreased with age. Bax/bcl2was the highest in sub-adults of male and female individuals. Caspase3 activity was the highest in sub-adults of male and female individuals, and the citrate synthase activity was highest in sub-adults of females. ATP synthase, citrate synthase, dynamin-related protein 1 and mitochondrial fission factor (Mff) were the highest in sub-adults of females. Peptidylglycine α-amidating monooxygenase were the highest in the aged group, and those of gonadotropin-releasing hormone was the highest in the adult group. LC3II/LC3I, P62, Drp1, Fis, and bax/bcl2 were higher in males than that in females. These results suggest that apoptosis mainly affects growth and development in the HG, whereas autophagy affects aging. The difference of the HG weight and mitochondrial function between sexes is mainly related to the apoptosis.

The effect of autophagy and mitochondrial fission on Harderian gland is greater than apoptosis in male hamsters during different photoperiods.

Photoperiod is an important factor of mammalian seasonal rhythm. Here, we studied morphological differences in the Harderian gland (HG), a vital photosensitive organ, in male striped dwarf hamsters (Cricetulus barabensis) under different photoperiods (short photoperiod, SP; moderate photoperiod, MP; long photoperiod, LP), and investigated the underlying molecular mechanisms related to these morphological differences. Results showed that carcass weight and HG weight were lower under SP and LP conditions. There was an inverse correlation between blood melatonin levels and photoperiod in the order SP > MP > LP. Protein expression of hydroxyindole-O-methyltransferase (HIOMT), a MT synthesis-related enzyme, was highest in the SP group. Protein expression of bax/bcl2 showed no significant differences, indicating that the level of apoptosis remained stable. Protein expression of LC3II/LC3I was higher in the SP group than that in the MP group. Furthermore, comparison of changes in the HG ultrastructure demonstrated autolysosome formation in the LP, suggesting the lowest autophagy level in under MP. Furthermore, the protein expression levels of ATP synthase and mitochondrial fission factor were highest in the MP group, whereas citrate synthase, dynamin-related protein1, and fission1 remained unchanged in the three groups. The change trends of ATP synthase and citrate synthase activity were similar to that of protein expression among the three groups. In summary, the up-regulation of autophagy under SP and LP may be a primary factor leading to loss of HG weight and reduced mitochondrial energy supply capacity.

TRPM8: A Therapeutic Target for Neuroinflammatory Symptoms Induced by Severe Dry Eye Disease.

Dry eye disease (DED) is commonly associated with ocular surface inflammation and pain. In this study, we evaluated the effectiveness of repeated instillations of transient receptor potential melastatin 8 (TRPM8) ion channel antagonist M8-B on a mouse model of severe DED induced by the excision of extra-orbital lacrimal and Harderian glands. M8-B was topically administered twice a day from day 7 until day 21 after surgery. Cold and mechanical corneal sensitivities and spontaneous ocular pain were monitored at day 21. Ongoing and cold-evoked ciliary nerve activities were next evaluated by electrophysiological multi-unit extracellular recording. Corneal inflammation and expression of genes related to neuropathic pain and inflammation were assessed in the trigeminal ganglion. We found that DED mice developed a cold allodynia consistent with higher TRPM8 mRNA expression in the trigeminal ganglion (TG). Chronic M8-B instillations markedly reversed both the corneal mechanical allodynia and spontaneous ocular pain commonly associated with persistent DED. M8-B instillations also diminished the sustained spontaneous and cold-evoked ciliary nerve activities observed in DED mice as well as inflammation in the cornea and TG. Overall, our study provides new insight into the effectiveness of TRPM8 blockade for alleviating corneal pain syndrome associated with severe DED, opening a new avenue for ocular pain management.

The Harderian gland: Endocrine function and hormonal control.

The Harderian gland (HG) is an exocrine gland located within the eye socket in a variety of tetrapods. During the 1980s and 1990s the HG elicited great interest in the scientific community due to its morphological and functional complexity, and from a phylogenetic point of view. A comparative approach has contributed to a better understanding of its physiology. Whereas the chemical nature of its secretions (mucous, serous or lipids) varies between different groups of tetrapods, the lipids represent the more common component among different species. Indeed, besides being an accessory to lubricate the nictitating membrane, the lipids may have a pheromonal function. Porphyrins and melatonin secretion is a feature of the rodent HG. The porphyrins, being phototransducers, could modulate HG melatonin production. The melatonin synthesis suggests an involvement of the HG in the retinal-pineal axis. Finally, StAR protein and steroidogenic enzyme activities in the rat HG suggests that the gland contributes to steroid hormone synthesis. Over the past twenty years, much has become known on the hamster (Mesocricetus auratus) HG, unique among rodents in displaying a remarkable sexual dimorphism concerning the contents of porphyrins and melatonin. Mainly for this reason, the hamster HG has been used as a model to compare, under normal conditions, the physiological oxidative stress between females (strong) and males (moderate). Androgens are responsible for the sexual dimorphism in hamster and they are known to control the HG secretory activity in different species. Furthermore, HG is a target of pituitary, pineal and thyroid hormones. This review offers a comparative panorama of the endocrine activity of the HG as well as the hormonal control of its secretory activity, with a particular emphasis on the sex dimorphic aspects of the hamster HG.

Simulating galactic cosmic ray effects: Synergy modeling of murine tumor prevalence after exposure to two one-ion beams in rapid sequence.

Health risks from galactic cosmic rays (GCR) in space travel above low earth orbit remain a concern. For many years accelerator experiments investigating space radiation induced prevalence of murine Harderian gland (HG) tumorigenesis have been performed to help estimate GCR risks. Most studies used acute, relatively low fluence, exposures. Results on a broad spectrum of individual ions and linear energy transfers (LETs) have become available. However, in space, the crew are exposed simultaneously to many different GCR. Recent upgrades at the Brookhaven NASA Space Radiation Laboratory (NSRL) now allow mixtures in the form of different one-ion beams delivered in rapid sequence. This paper uses the results of three two-ion mixture experiments to illustrate conceptual, mathematical, computational, and statistical aspects of synergy analyses and also acts as an interim report on the mixture experiments' results. The results were interpreted using the following: (a) accumulated data from HG one-ion accelerator experiments; (b) incremental effect additivity synergy theory rather than simple effect additivity synergy theory; (c) parsimonious models for one-ion dose-effect relations; and (d), computer-implemented numerical methods encapsulated in freely available open source customized software. The main conclusions are the following. As yet, the murine HG tumorigenesis experimental studies show synergy in only one case out of three. Moreover, some theoretical arguments suggest GCR-simulating mixed beams are not likely to be synergistic. However, more studies relevant to possible synergy are needed by various groups that are studying various endpoints. Especially important is the possibility of synergy among high-LET radiations, since individual high-LET ions have large relative biological effectiveness for many endpoints. Selected terminology, symbols, and abbreviations. DER - dose-effect relation; E(d) - DER of a one-ion beam, where d is dose; HG prevalence p - in this paper, p is the number of mice with at least one Harderian gland tumor divided by the number of mice that are at risk of developing Harderian gland tumors (so that in this paper prevalence p can never, conceptually speaking, be greater than 1); IEA - incremental effect additivity synergy theory; synergy level - a specification, exemplified in Fig. 5, of how clear-cut an observed synergy is; mixmix principle - a consistency condition on a synergy theory which insures that the synergy theory treats mixtures of agent mixtures in a mathematically self-consistent way; NTE - non-targeted effect(s); NSNA - neither synergy nor antagonism; SEA - simple effect additivity synergy theory; TE - targeted effect(s); ß* - ion speed relative to the speed of light, with 0 < ß* < 1; SLI - swift light ion(s).

Immunomodulatory effect of ginseng stem-leaf saponins and selenium on Harderian gland in immunization of chickens to Newcastle disease vaccine.

Our previous study demonstrated that ginseng stem-leaf saponins (GSLS) in combination with selenium (GSLS-Se) have adjuvant effect on the live vaccine of Newcastle disease virus (NDV) and infectious bronchitis virus (IBV) in intraocular-and-intranasal immunization in chickens. The present study was to investigate the potential molecular mechanisms involved in the immunomodulation of GSLS-Se on the Harderian gland (HG). It was found that the window allowing animals susceptible to infections due to low antibody titers became smaller or even completely closed because of increased NDV-specific HI titers when NDV vaccine and GSLS-Se were coadministered for immunization at early life in chickens. In addition, NDV-specific sIgA and the numbers of IgG+, IgA+, IgM+ plasma cells were significantly more in GSLS-Se group than the control in the HGs. Transcriptome analysis of HGs identified 1184 differentially expressed genes (DEGs) between GSLS-Se treated and non-treated groups. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses identified 42 significantly enriched GO terms and 13 canonical immune pathways. These findings indicated that GSLS-Se might exert immunomodulatory effects through influencing the antioxidant regulation and modulating the activity of immune related enzymes. Besides, Toll-like receptor (TLR) signaling pathway and mitogen-activated protein kinase (MAPK) signaling pathway might be involved primarily in the immunomodulation. Therefore, enhanced antibody responses in GSLS-Se group may be attributed to the immunomodulatory effects of GSLS-Se on the immune-related gene profile expressed in the immunocompetent cells of the HGs.

Histopathological changes in tear-secreting tissues and cornea in a mouse model of autoimmune disease.

IMPACT STATEMENT: Cornea, an outermost layer of mammalian eye, is protected by tear film and abnormalities of tear film causes dry eye. Dry eye injures the cornea which results lower vision in patients. Several factors cause dry eye, including altered systemic conditions, environment, and immunological abnormality of the patient in autoimmune disease like Sjögren's syndrome (SS). However, the detailed pathology of autoimmune abnormality-mediated dry eye is unclear. Here we demonstrated that systemic autoimmune abnormality in BXSB-Yaa mice was associated with histological changes in the exocrine glands and cornea of the eyes. We also showed that BXSB-Yaa mice developed mild or early stage dry eye-like disease and explain the existence of a compensatory mechanism associated with the dysfunction of these tissues. Thus, BXSB-Yaa could be a model for SS-like disease-associated dry eye and these data would contribute to the understanding of the pathogenesis of autoimmune-related dry eye disease.

Assessing Nonlinearity in Harderian Gland Tumor Induction Using Three Combined HZE-irradiated Mouse Datasets.

Recently reported studies considering nonlinearity in the effects of low-dose space radiation have assumed a nontargeted mechanism. To date, few analyses have been performed to assess whether a nontargeted term is supported by the available data. The Harderian gland data from Alpen et al. (published in 1993 and 1994), and Chang et al. (2016) provide the most diversity of ions and energies in a tumor induction model, including multiple high-energy and charge particles. These data can be used to investigate various nonlinearity assumptions against a linear model, including nontargeted effects in the low-dose region or cell sterilization at high doses. In this work, generalized linear models were used with the log complement link function to analyze the binomial data from the studies independently and combined. While there was some evidence of nonlinearity that was best described by a cell-sterilization model, the linear model was adequate to describe the data. The current data do not support the addition of a nontargeted effects term in any model. While adequate data are available in the low-dose region (<0.5 Gy) to support a nontargeted effects term if valid, additional data in the 1-2 Gy region are necessary to achieve power for cell-sterilization analysis validation. The current analysis demonstrates that the Harderian gland tumor data do not support the use of a nontargeted effects term in human cancer risk models.