Effects of Diabetes and Voluntary Exercise on IgA Concentration and Polymeric Immunoglobulin Receptor Expression in the Submandibular Gland of Rats.

Background and Objectives: Patients with diabetes are more susceptible to upper respiratory tract infections (URTIs) because they are easily infected. Salivary IgA (sali-IgA) levels play a major role in transmitting URTIs. Sali-IgA levels are determined by salivary gland IgA production and polymeric immunoglobulin receptor (poly-IgR) expression. However, it is unknown whether salivary gland IgA production and poly-IgR expression are decreased in patients with diabetes. While exercise is reported to increase or decrease the sali-IgA levels, it is unclear how exercise affects the salivary glands of patients with diabetes. This study aimed to determine the effects of diabetes and voluntary exercise on IgA production and poly-IgR expression in the salivary glands of diabetic rats. Materials and Methods: Ten spontaneously diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats (eight-week-old) were divided into two groups of five rats each: a non-exercise group (OLETF-C) and a voluntary wheel-running group (OLETF-E). Five Long-Evans Tokushima Otsuka (LETO) rats without diabetes were bred under the same conditions as the OLETF-C. Sixteen weeks after the study began, the submandibular glands (SGs) were collected and analyzed for IgA and poly-IgR expression levels. Results: IgA concentrations and poly-IgR expression levels in SGs were lower in OLETF-C and OLETF-E than in LETO (p < 0.05). These values did not differ between the OLETF-C and OLETF-E. Conclusions: Diabetes decreases IgA production and poly-IgR expression in the salivary glands of rats. Moreover, voluntary exercise increases sali-IgA levels but does not increase IgA production and poly-IgR expression in the salivary glands of diabetic rats. Increasing IgA production and poly-IgR expression in the salivary glands, which is reduced in diabetes, might require slightly higher-intensity exercise than voluntary exercise under the supervision of a doctor.

Vitamin C and eggshell membrane facilitate orthodontic tooth movement and induce histological changes in the periodontal tissue.

OBJECTIVES: Collagen remodeling of the periodontal tissue is an important mechanism that involves several biologically active substances to accelerate orthodontic tooth movement. It is known that Vitamin C (VC) enhances collagen production and induces tooth movement. Moreover, the eggshell membrane (ESM) is an integral component of various formulations used to promote wound healing. The purpose of our study was to determine the effects of combined treatment with VC and ESM on periodontal tissues during tooth movement. METHODS: Nine-week-old male osteogenic disorder Shionogi rats were randomized into four groups: control, VC, ESM, and VC + ESM. The control group was given tap water, and the VC, ESM, and VC + ESM groups were orally administered 0.1% VC solution, 1 wt% ESM solution, and a combination of 0.1 wt% VC and 1 wt% ESM solutions, respectively. A force of 25 or 75 g was applied for 10 days to produce orthodontic tooth movement. Distances of tooth movement were measured on days 3, 7, and 10 of treatment. Histological examination of the periodontal ligament was performed to determine the increase in type I and III collagen levels in response to treatment. RESULTS: Distances of tooth movement were significantly greater in the VC + ESM group than in the control group. The compression area of the alveolar bone showed increased osteoclastic activity and higher levels of bone resorption in the VC + ESM group. Expression levels of type I and III collagen in the tension area of the alveolar bone were higher in the VC + ESM group than in the control group. CONCLUSIONS: This study revealed that the combined administration of VC and ESM accelerated tooth movement by protecting the periodontal tissue during orthodontic treatment. The combined clinical application of VC and ESM could potentially shorten orthodontic treatment time.

Correction of Mass Spectrometric Interferences for Rapid and Precise Isotope Ratio Measurements of Calcium from Biological Samples Using ICP-Mass Spectrometry.

Stable isotope compositions of calcium (Ca) provide useful information concerning metabolic alterations of Ca in human and animal bodies. For the measurements of Ca isotope ratio, great care must be taken for the mass spectrometric interferences on Ca isotopes (42Ca+, 43Ca+, and 44Ca+) from doubly charged strontium (Sr) ions (84Sr2+, 86Sr2+, and 88Sr2+). To obtain reliable stable isotope data of Ca, we developed a new correction technique for the mass spectrometric interferences by mSr2+ ions based on standard addition method. Addition of a small fraction of Sr onto a Ca solution shifts the measured Ca isotope ratios on a three-isotope diagram (i.e., δ44Ca and δ43Ca) along a mixing line defined by both the true Ca isotope ratio and the Sr isotope ratio. Therefore, the true Ca isotope ratio of a sample can be obtained as the crossover point of mass dependent fractionation line and the mixing line. With the present correction technique, precise and accurate isotope ratio measurements can be made on analyte solutions having a CSr/CCa ratio (concentration ratio) of 0.03, which is 6 times higher than the CSr/CCa ratio applicable to the conventional correction technique.

Low-Intensity Pulsed Ultrasound Prevents Development of Bisphosphonate-Related Osteonecrosis of the Jaw-Like Pathophysiology in a Rat Model.

We developed a rat model of bisphosphonate-related osteonecrosis of the jaw (BRONJ) by removing a maxillary molar tooth (M1) from ovariectomized rats after treatment with alendronate. To mimic periodontitis, some of the rats were administered Porphyromonas gingivalis (p. gingivalis) at the M1 site every 2 to 3 d for 2 wk. Rats pretreated with alendronate plus p. gingivalis showed delayed healing of socket epithelia, periosteal reaction of alveolar bone formation and lower bone mineral density in the alveolus above adjacent M2 teeth. These abnormalities were prevented by tooth socket exposure to 20 min/d low-intensity pulsed ultrasound (LIPUS), which restored diminished expression of RANKL, Bcl-2, IL-6, Hsp70, NF-κB and TNF-α messenger ribonucleic acids in remote bone marrow, suggesting LIPUS prevented development of BRONJ-like pathophysiology in rat by inducing systemic responses for regeneration, in addition to accelerating local healing. Non-invasive treatment by LIPUS, as well as low-level laser therapy, may be useful for medication-related osteonecrosis of the jaw patients.

Effect of advanced platelet-rich fibrin on accelerating alveolar bone formation in dogs: a histological and immunofluorescence evaluation.

Several methods have been developed to regenerate lost alveolar bone. Platelet-rich fibrin (PRF) is a useful adjunct for new bone formation in dentistry. To elucidate the effect of advanced PRF (A-PRF) on bone formation, we inserted A-PRF clots in sockets after tooth extraction. Premolars were extracted from beagle dogs, and A-PRF was applied to the socket. New bone formation was assessed using histological and immunofluorescence examinations, and the bone formation ratio was evaluated 14 and 30 days postoperatively. Histological examination revealed newly formed bone filling the sockets up to the center in the A-PRF group at 14 days postoperatively, while thick and regular bone trabeculae were arranged in porous bone after 30 days. Higher expressions of osteocalcin and osteopontin were observed in newly formed bone in the A-PRF group, compared to the control group. The bone formation ratio was also higher in the A-PRF group than in the control group. Thus, A-PRF application may result in enhanced new bone formation and may aid in accelerating bone formation. A-PRF was more rapid than a self-limiting process during induction of bone formation by enhancing osteoblast activity and may be useful for bone formation in clinical medicine.

13. Effect of Low-Intensity Pulsed Ultrasound (LIPUS) on Remote Bone Marrow in Rats With Healing Socket.

OBJECTIVE: We reported at the previous annual meeting that LIPUS treatment of the molar tooth sockets of retired breeder rats accelerated alveolar bone healing, and that associated humoral effects were seen with elevated blood flow. Namely, LIPUS induced VEGF/angiogenesis along with elevated baseline blood flow rate, which was further associated with a sudden depression of blood flow rate in the socket immediately after cessation of LIPUS treatment. Prior injection with EP4 PGE2 receptor antagonist, but not EP3 antagonist, abolished this LIPUS-induced depression, and topical application of PGE2 to the socket epithelium mimicked the LIPUS-induced depression. In fact, the serum level of PGE2 increased after LIPUS treatment, and significantly increased in the blood flow rate at remote sites on the foot dorsum and tail after 20 minutes. Therefore, in the current study, we examined the tibia bone marrow, which is likely to respond to circulating PGE2. METHODS: Right maxillary first molars were removed from retired female breeder rats in both the LIPUS and the control groups. LIPUS was applied extrabuccally to the socket every 24 hours for 2 weeks starting one day after extraction. Removed bone samples were fixed with 4% formaldehyde to prepare undecalcified frozen sections using Kawamoto's method for immunohistochemical or histochemical staining. Bone marrow samples dissected from the tibia were treated with RNAlater (Ambion) for later RT-PCR analysis. RESULTS AND DISCUSSION: Chemokine receptor CXCR4-positive bone marrow cells increased in the tibia of the LIPUS-treated rat. Together with ubiquitously expressed CXCL12(SDF-1), it is suggested that PGE2 released from the exposed socket is responsible for the recruitment, proliferation and mobilization of the precursors of bone forming cells. LIPUS is thought to exert humoral effects by recruiting bone marrow cells into the healing socket along with VEGF/angiogenesis induced by PGE2.

Daily Intake of Heat-killed Lactobacillus plantarum L-137 Decreases the Probing Depth in Patients Undergoing Supportive Periodontal Therapy.

PURPOSE: Heat-killed Lactobacillus plantarum L-137 (HK L-137) has been shown to activate innate and acquired immunity in humans. The aim of this randomised, double-blind, placebo-controlled clinical trial was to examine the effects of the oral administration of HK L-137 on the outcome of periodontal therapy. MATERIALS AND METHODS: Thirty-nine patients undergoing supportive periodontal therapy (SPT) were randomly assigned to receive a capsule containing 10 mg of HK L-137 or a placebo capsule daily for 12 weeks. Nineteen patients in the experimental group and 17 patients in the control group were followed-up. Clinical parameters, including plaque index (PI), gingival index (GI), bleeding on probing (BOP), and probing depth (PD) were scored at baseline and weeks 4, 8 and 12 prior to prophylaxis in conjunction with regular SPT visits. RESULTS: BOP and the number of teeth or sites with PD ≥ 4 mm were significantly reduced in both groups by a successive SPT programme, while there was significantly greater PD reduction (p < 0.05) at teeth with site(s) with PD ≥ 4 mm at baseline in the experimental group than in the control group at week 12. CONCLUSION: These clinical findings suggest that daily HK L-137 intake can decrease the depth of periodontal pockets in patients undergoing supportive periodontal therapy.

Fasudil, a Rho kinase inhibitor, suppresses tumor growth by inducing CXCL14/BRAK in head and neck squamous cell carcinoma.

CXCL14/BRAK (BRAK) is a secreted chemokine with anti-tumor activity, and its expression is suppressed in tumor cells. We previously reported the anti-tumor activity of BRAK in cell lines of head and neck squamous cell carcinoma (HNSCC) and the suppression of BRAK secretion in these cells. BRAK secretion in fibrosarcoma cells is restored by Fasudil, which is a Rho-kinase (ROCK) inhibitor. In this study, we examined the anti-tumor effect of BRAK by evaluating its gene expression and protein secretion in HNSCC cell lines. We found that BRAK mediated the suppressive effect of Fasudil against HNSCC cells. Tumor development in female BALB/cAJclnu/nu mice was suppressed by Fasudil. Also secretion of BRAK protein by tumor cell lines in vitro was significantly stimulated by Fasudil treatment. Similarly, the production of BRAK protein was significantly increased by the addition of Fasudil to cultured tumor cells. Furthermore Fasudil significantly increased BRAK gene expression at the mRNA level in HNSCC cell line. Inhibition of the RhoA/ROCK pathway by siRNAs significantly stimulated BRAK gene expression. These results show that the tumor-suppressive effect of Fasudil was mediated by BRAK, suggesting that Fasudil may therefore be useful for the treatment of HNSCC.