Oral supplementation with p-coumaric acid protects mice against diabetes-associated spontaneous destruction of periodontal tissue

Poly(p-coumaric acid) nanoparticles alleviate temporomandibular joint osteoarthritis by inhibiting chondrocyte ferroptosis

Oxidative stress and inflammation are key drivers of osteoarthritis (OA) pathogenesis and disease progression. Herein we report the synthesis of poly(p-coumaric) nanoparticles (PCA NPs) from p-courmaic acid (p-CA), a naturally occurring phytophenolic acid, to be a multifunctional and drug-free therapeutic for temporomandibular joint osteoarthritis (TMJOA). Compared to hyaluronic acid (HA) that is clinically given as viscosupplementation, PCA NPs exhibited long-term efficacy, superior anti-oxidant and anti-inflammatory properties in alleviating TMJOA and repairing the TMJ cartilage and subchondral bone in a rat model of TMJOA. Notably, TMJ repair mediated by PCA NPs could be attributed to their anti-oxidant and anti-inflammatory properties in enhancing cell proliferation and matrix synthesis, while reducing inflammation, oxidative stress, matrix degradation, and chondrocyte ferroptosis. Overall, our study demonstrates a multifunctional nanoparticle, synthesized from natural p-coumaric acid, that is stable and possess potent antioxidant, anti-inflammatory properties and ferroptosis inhibition, beneficial for treatment of TMJOA.

Characterisation and Expression of Osteogenic and Periodontal Markers of Bone Marrow Mesenchymal Stem Cells (BM-MSCs) from Diabetic Knee Joints

Type 2 diabetes mellitus (T2DM) represents a significant health problem globally and is linked to a number of complications such as cardiovascular disease, bone fragility and periodontitis. Autologous bone marrow mesenchymal stem cells (BM-MSCs) are a promising therapeutic approach for bone and periodontal regeneration; however, the effect of T2DM on the expression of osteogenic and periodontal markers in BM-MSCs is not fully established. Furthermore, the effect of the presence of comorbidities such as diabetes and osteoarthritis on BM-MSCs is also yet to be investigated. In the present study, BM-MSCs were isolated from osteoarthritic knee joints of diabetic and nondiabetic donors. Both cell groups were compared for their clonogenicity, proliferation rates, MSC enumeration and expression of surface markers. Formation of calcified deposits and expression of osteogenic and periodontal markers were assessed after 1, 2 and 3 weeks of basal and osteogenic culture. Diabetic and nondiabetic BM-MSCs showed similar clonogenic and growth potentials along with comparable numbers of MSCs. However, diabetic BM-MSCs displayed lower expression of periostin (POSTN) and cementum protein 1 (CEMP-1) at Wk3 osteogenic and Wk1 basal cultures, respectively. BM-MSCs from T2DM patients might be suitable candidates for stem cell-based therapeutics. However, further investigations into these cells' behaviours in vitro and in vivo under inflammatory environments and hyperglycaemic conditions are still required.

P-coumaric Acid: Advances in Pharmacological Research Based on Oxidative Stress

P-coumaric acid is an important phenolic compound that is mainly found in fruits, vegetables, grains, and fungi and is also abundant in Chinese herbal medicines. In this review, the pharmacological research progress of p-coumaric acid in recent years was reviewed, with emphasis on its role and mechanism in oxidative stress-related diseases, such as inflammation, cardiovascular diseases, diabetes, and nervous system diseases. Studies have shown that p-coumaric acid has a positive effect on the prevention and treatment of these diseases by inhibiting oxidative stress. In addition, p-coumaric acid also has anti-tumor, antibacterial, anti-aging skin and other pharmacological effects. This review will provide reference and inspiration for further research on the pharmacological effects of p-coumaric acid.

G. A, Al-Rawi AM, Nassar R, Islam MS. Phytic acid effect on periodontal ligament fibroblast: An in-vitro study

OBJECTIVES

This study evaluated phytic acid (IP6) effect on the viability, alkaline phosphatase (ALP) activity and calcium release of human periodontal ligament (HPDL) cells in optimal (OGL) and elevated glucose level (EGL) in cell culture media.

MATERIALS AND METHODS

Cells were seeded in OGL (1000mg/L) or EGL (4500 mg/L) media. IP6 was added at 0.005%, 0.01% or 0.02% concentrations for 24 or 48h, and XTT assay was performed. Cell differentiation and calcium release in presence of 0.02% IP6 in OGL or EGL in non-osteogenic or osteogenic media were analyzed using ALP assay and alizarin red staining, respectively.

RESULTS

In OGL, IP6 enhanced the viability of the cells at both exposure times (P<0.05). However, IP6 lowered the viability of the cells with the presence of EGL compared to the control at both exposure times, except for 0.02% IP6 which showed comparable viability to the control at 48 h. In OGL and EGL, ALP activity of the cells was not affected by the presence of IP6 in non-osteogenic media; however, in osteogenic media IP6 lowered the ALP activity. Meanwhile, calcium release was the highest with IP6 within osteogenic media of EGL.

CONCLUSIONS

IP6 effects on the HPDL cells were dependent on IP6 concentration, time of exposure, glucose levels and the osteogenic condition of the media.

CLINICAL RELEVANCE

This study gives insights on the potential therapeutic effect of IP6 as adjunctive periodontal therapy in patients with diabetes.

Recent progress in bone-repair strategies in diabetic conditions

Bone regeneration following trauma, tumor resection, infection, or congenital disease is challenging. Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia. It can result in complications affecting multiple systems including the musculoskeletal system. The increased number of diabetes-related fractures poses a great challenge to clinical specialties, particularly orthopedics and dentistry. Various pathological factors underlying DM may directly impair the process of bone regeneration, leading to delayed or even non-union of fractures. This review summarizes the mechanisms by which DM hampers bone regeneration, including immune abnormalities, inflammation, reactive oxygen species (ROS) accumulation, vascular system damage, insulin/insulin-like growth factor (IGF) deficiency, hyperglycemia, and the production of advanced glycation end products (AGEs). Based on published data, it also summarizes bone repair strategies in diabetic conditions, which include immune regulation, inhibition of inflammation, reduction of oxidative stress, promotion of angiogenesis, restoration of stem cell mobilization, and promotion of osteogenic differentiation, in addition to the challenges and future prospects of such approaches.

Periodontal Health and Disease in the Context of Systemic Diseases

During recent years, considerable progress has been made in understanding the etiopathogenesis of periodontitis in its various forms and their interactions with the host. Furthermore, a number of reports have highlighted the importance of oral health and disease in systemic conditions, especially cardiovascular diseases and diabetes. In this regard, research has attempted to explain the role of periodontitis in promoting alteration in distant sites and organs. Recently, DNA sequencing studies have revealed how oral infections can occur in distant sites such as the colon, reproductive tissues, metabolic diseases, and atheromas. The objective of this review is to describe and update the emerging evidence and knowledge regarding the association between periodontitis and systemic disease and to analyse the evidence that has reported periodontitis as a risk factor for the development of various forms of systemic diseases in order to provide a better understanding of the possible shared etiopathogenetic pathways between periodontitis and the different forms of systemic diseases.

Oxidative stress in human gingival fibroblasts from periodontitis versus healthy counterparts

OBJECTIVE

Elevated p53 promotes oxidative stress and production of pro-inflammatory cytokines in liposaccharide (LPS)-treated healthy human gingival fibroblasts (HGFs). This study compared oxidative stress, production of inflammatory cytokines, and p53 expression in HGFs from patients with chronic periodontitis (CP) and healthy subjects in vitro upon LPS from Porphyromonas gingivalis challenge.

METHODS

Human gingival fibroblasts were isolated from 6 biopsies-3 from healthy donors and 3 from diseased area in CP (Grade B, Stage III). HGFs were cultured with or without 1 μg/ml 24 h LPS. Oxidative stress was assessed by analyzing the level of reactive oxygen species (ROS). Mitochondrial membrane potential and respiration were determined by immunofluorescence and respirometry, respectively. Tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β were determined by enzyme-linked immunosorbent assay. P53 expression was monitored by Western blot and immunofluorescence.

RESULTS

Human gingival fibroblasts from CP exhibited increased levels of mitochondrial p53, enhanced ROS production, decreased mitochondrial membrane potential, increased mitochondrial oxygen consumption, and increased secretion of TNF-α, IL-6, and IL-1β, as compared to HGFs from healthy donors. Moreover, LPS exacerbated these changes.

CONCLUSION

Human gingival fibroblasts from CP exhibited stronger basal and LPS-inducible oxidative stress and inflammatory response as compared to HGFs from healthy subjects by increased p53 in mitochondria.

Onopordum acanthium L. extract attenuates pancreatic β-Cells and cardiac inflammation in streptozocin-induced diabetic rats

BACKGROUND AND OBJECTIVE

Methanolic extract from Onopordum acanthium L. leaves (MEOAL) has been discovered to treat diabetic complications. The objective of this study is to evaluate the ameliorative role of MEOAL on pancreatic islet injury and myocardial inflammation in diabetic rats.

METHODS

Forty male Wister albino rats were allocated into five groups of eight rats each. Group A was the negative control group. Single intraperitoneal injection of streptozocin (50mg/kg) were used for the four experimental groups. Group B served as the positive control group. The rats in Groups C, D, and E received glibenclamide (5mg/kg), MEOAL (200, and 400 mg/kg) respectively, for eight weeks. Group C served as the standard drug group. High performance liquid chromatography (HPLC) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assays for antioxidant activity were conducted in MEOAL. In silico study, calculation of molecular binding energy (DG), and inhibition constant (pKi) of bioactive constituents in MEOAL were performed.

RESULTS

Administration of MEOAL significantly increases insulin content in β-cells with a marked enhancement of pancreatic islet structure, resulting in a significant reduction of blood glucose level and body weight loss. MEOAL treatment suppressed the increase of inflammatory cell score in myocardial tissue with an elevation of M2 -like macrophage. The phytochemical studies recorded the presence of six polyphenols, including catechin, kaempferol, syringic acid, p-coumaric acid, epicatechin and gallic acid in MEOAL. Moreover, the antioxidant activity of the extract was greater than that of standard ascorbic acid. The docking studies of the ligands Catechin, kaempferol and epicatechin with proteins showed high affinities with various targets related in β-Cells and cardiac inflammation.

CONCLUSIONS

The attenuation of pancreatic β-Cells damage and cardiac inflammation by MEOAL could be attributed to the presence of Catechin, kaempferol and epicatechin which have high affinities with the receptors namely pancreatic alpha-amylase, glucokinase, COX-2, and COX-1.

Chitosan–Hydroxycinnamic Acids Conjugates: Emerging Biomaterials with Rising Applications in Biomedicine

Over the past thirty years, research has shown the huge potential of chitosan in biomedical applications such as drug delivery, tissue engineering and regeneration, cancer therapy, and antimicrobial treatments, among others. One of the major advantages of this interesting polysaccharide is its modifiability, which facilitates its use in tailor-made applications. In this way, the molecular structure of chitosan has been conjugated with multiple molecules to modify its mechanical, biological, or chemical properties. Here, we review the conjugation of chitosan with some bioactive molecules: hydroxycinnamic acids (HCAs); since these derivatives have been probed to enhance some of the biological effects of chitosan and to fine-tune its characteristics for its application in the biomedical field. First, the main characteristics of chitosan and HCAs are presented; then, the currently employed conjugation strategies between chitosan and HCAs are described; and, finally, the studied biomedical applications of these derivatives are discussed to present their limitations and advantages, which could lead to proximal therapeutic uses.

p-Coumaric acid attenuates high-fat diet-induced oxidative stress and nephropathy in diabetic rats

The prevalence of persistent hyperglycaemia during diabetes, impair antioxidant defence system and generate reactive oxygen species, which majorly contribute to its progression and associated complications. Phytochemicals were suggested to scavenge-free radicals and exert antioxidant effects required to improve insulin sensitivity and reduce the occurrence of diabetes-associated complications. We hypothesise that a phenolic phytochemical p-coumaric can reduce diabetes-induced oxidative stress and improve diabetes-associated nephropathy in rats. The aim of this study is to analyse the protective effects of p-coumaric acid against diabetes-induced oxidative stress and nephropathy in high-fat diet-induced diabetic rats. The oral feeding of p-coumaric acid (20 mg/kg for 12 weeks) was found to significantly decrease the elevated levels of blood glucose in high-fat diet-induced type 2 diabetic rats. p-Coumaric acid treatment also decreases the kidney weight whilst increasing the total body weight of diabetic rats. Furthermore whilst evaluation of the different renal functioning tests, p-coumaric acid significantly improves histopathological changes and the levels of urea, creatinine and uric acid in serum of diabetic rats, which was otherwise elevated under diabetic conditions. Our results also highlight that p-coumaric acid is an efficient compound with antioxidant properties and improves the diabetes-induced change in lipid peroxidation and activities of antioxidant enzymes: catalase, glutathione-S-transferase and superoxide dismutase. p-Coumaric acid thus possesses the potential to prevent diabetic nephropathy by reducing oxidative stress and can thus serve as a potential drug target for pharmaceutical companies.

Ethanolic extract from the root and leaf of Sida cordifolia promotes osteoblast activity and prevents ovariectomy-induced bone loss in mice

BACKGROUND

Sida cordifolia is traditionally found in the Indian system of medicine, well known for its medicinal and nutritional properties among local natives.

PURPOSE

The present study aims to investigate the osteo-protective effect of root and leaf ethanolic extract of S. cordifolia (RE and LE) and its underlying mechanism.

METHODS

Antioxidant activity of RE and LE was assessed. Total phenolic and flavonoid content were determined. HPLC profiling of RE and LE was performed to examine the polyphenol content. The effect of RE and LE on osteoblast cells proliferation, differentiation, mineralization, and expression of the protein associated with osteogenesis were evaluated using primary calvarial osteoblast culture. Skeletal effects of RE and LE of S. cordifolia were investigated in C57BL/6J ovariectomized mice. Micro CT was employed to evaluate the alteration in trabecular and cortical bone microarchitecture. Histology studies were performed on the isolated vertebra. qPCR analysis and western blotting was done to check the key bone markers.

RESULTS

RE and LE showed a potent antioxidant activity, owing to a notable polyphenol content. Both RE and LE did not alter the cell viability but significantly increased the osteoblast cell proliferation, differentiation, and mineralization. Moreover, they enhanced the mRNA expression of osteogenic genes. Both RE and LE stimulated the activation of ERK, AKT, and CREB. Both RE and LE had no direct effect on osteoclastogenesis, but both increased Opg/Rankl ratio expression in osteoblast cells. Both RE and LE at 750 mg/kg/day significantly improved the trabecular and cortical microarchitecture of femur and tibia by increasing bone mineral density, bone volume fraction, trabecular number, and trabecular thickness, and decreasing trabecular separation and structural model index in ovariectomized mice. Furthermore, vertebral histology of lumbar vertebrae revealed that RE and LE significantly enhance the vertebral bone mass and exert osteo-protective effects by stimulating osteoblast function and inhibiting osteoclast function.

CONCLUSION

In conclusion, both RE and LE stimulate osteoblast differentiation through activating ERK, AKT, and CREB signalling pathways and indirectly inhibits osteoclast differentiation. RE and LE also improve the trabecular and cortical microarchitecture of ovariectomized mice, making it a promising agent to prevent postmenopausal bone loss.

The Effect of Diabetes Mellitus on IGF Axis and Stem Cell Mediated Regeneration of the Periodontium

Periodontitis and diabetes mellitus (DM) are two of the most common and challenging health problems worldwide and they affect each other mutually and adversely. Current periodontal therapies have unpredictable outcome in diabetic patients. Periodontal tissue engineering is a challenging but promising approach that aims at restoring periodontal tissues using one or all of the following: stem cells, signalling molecules and scaffolds. Mesenchymal stem cells (MSCs) and insulin-like growth factor (IGF) represent ideal examples of stem cells and signalling molecules. This review outlines the most recent updates in characterizing MSCs isolated from diabetics to fully understand why diabetics are more prone to periodontitis that theoretically reflect the impaired regenerative capabilities of their native stem cells. This characterisation is of utmost importance to enhance autologous stem cells based tissue regeneration in diabetic patients using both MSCs and members of IGF axis.

Astaxanthin Inhibits Diabetes-Triggered Periodontal Destruction, Ameliorates Oxidative Complications in STZ-Injected Mice, and Recovers Nrf2-Dependent Antioxidant System

Numerous studies highlight that astaxanthin (ASTX) ameliorates hyperglycemic condition and hyperglycemia-associated chronic complications. While periodontitis and periodontic tissue degradation are also triggered under chronic hyperglycemia, the roles of ASTX on diabetes-associated periodontal destruction and the related mechanisms therein are not yet fully understood. Here, we explored the impacts of supplemental ASTX on periodontal destruction and systemic complications in type I diabetic mice. To induce diabetes, C57BL/6 mice received a single intraperitoneal injection of streptozotocin (STZ; 150 mg/kg), and the hyperglycemic mice were orally administered with ASTX (12.5 mg/kg) (STZ+ASTX group) or vehicle only (STZ group) daily for 60 days. Supplemental ASTX did not improve hyperglycemic condition, but ameliorated excessive water and feed consumptions and lethality in STZ-induced diabetic mice. Compared with the non-diabetic and STZ+ASTX groups, the STZ group exhibited severe periodontal destruction. Oral gavage with ASTX inhibited osteoclastic formation and the expression of receptor activator of nuclear factor (NF)-κB ligand, 8-OHdG, γ-H2AX, cyclooxygenase 2, and interleukin-1β in the periodontium of STZ-injected mice. Supplemental ASTX not only increased the levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and osteogenic transcription factors in the periodontium, but also recovered circulating lymphocytes and endogenous antioxidant enzyme activity in the blood of STZ-injected mice. Furthermore, the addition of ASTX blocked advanced glycation end products-induced oxidative stress and growth inhibition in human-derived periodontal ligament cells by upregulating the Nrf2 pathway. Together, our results suggest that ASTX does not directly improve hyperglycemia, but ameliorates hyperglycemia-triggered periodontal destruction and oxidative systemic complications in type I diabetes.

Scavenging Properties of Plant-Derived Natural Biomolecule Para-Coumaric Acid in the Prevention of Oxidative Stress-Induced Diseases

Para-coumaric acid (p-CA) is a plant derived secondary metabolite belonging to the phenolic compounds. It is widely distributed in the plant kingdom and found mainly in fruits, vegetables, and cereals. Various in vivo and in vitro studies have revealed its scavenging and antioxidative properties in the reduction of oxidative stress and inflammatory reactions. This evidence-based review focuses on the protective role of p-CA including its therapeutic potential. p-CA and its conjugates possesses various bioactivities such as antioxidant, anti-inflammatory, anti-cancer, anti-diabetic, and anti-melanogenic properties. Due to its potent free radical scavenging activity, it can mitigate the ill effects of various diseases including arthritis, neurological disorders, and cardio-vascular diseases. Recent studies have revealed that p-CA can ameliorate the harmful effects associated with oxidative stress in the reproductive system, also by inhibiting enzymes linked with erectile function.

Hydroxycoumarin Scopoletin Inhibits Bone Loss through Enhancing Induction of Bone Turnover Markers in a Mouse Model of Type 2 Diabetes

Diabetes induces bone deterioration, which leads to increased risk of fracture, osteopenia, and osteoporosis. Thus, diabetes-associated bone fragility has been recognized as a diabetic complication. However, the pathophysiological effects of hyperglycemia on bone turnover remain unclear. Literature evidence demonstrates that anti-diabetic medications increase the risk of fractures in individuals with type 2 diabetes. Scopoletin is a naturally occurring hydroxycoumarin potentially exhibiting anti-inflammatory and antioxidant activities and ameliorating insulin resistance as an anti-diabetic agent. However, little is known regarding the effects of scopoletin on the impairment of bone remodeling that is caused by diabetes. The aim of this study was to identify that scopoletin was capable of inhibiting the impairment of bone remodeling and turnover in a mouse model of type 2 diabetes. Submicromolar scopoletin accelerated the formation TRAP-positive multinucleated osteoclasts (40.0 vs. 105.1%) and actin ring structures impaired by 33 mM glucose. Further, 1–20 μM scopoletin enhanced bone resorption and the induction of matrix-degrading enzymes in diabetic osteoclasts. The oral administration of 10 mg/kg scopoletin elevated serum RANKL/OPG ratio and osteocalcin level reduced in db/db mice along with an increase in BMD by ~6–14%; however, it was not effective in lowering blood glucose and hemoglobin glycation. In addition, the supplementation of scopoletin elevated the formation of trabecular bones and collagen fibers in femoral epiphysis and metaphysis with a thicker epiphyseal plate and cortical bones. Furthermore, 1–20 μM scopoletin enhanced ALP activity (4.39 vs. 7.02 nmol p-nitrophenyl phosphate/min/mg protein) and deposits of mineralized bone nodules in cultured osteoblasts reduced by 33 mM glucose. The treatment of diabetic osteoblasts with scopoletin stimulated the cellular induction of BMP-2 and osteopontin and Runx2 transcription. Accordingly, the administration of scopoletin protected mice from type 2 diabetes-associated bone loss through boosting bone remodeling via the robust induction of bone turnover markers of both osteoclasts and osteoblasts. These findings suggest that scopoletin could be a potential osteoprotective agent for the treatment of diabetes-associated bone loss and fractures.

Identification of the different salivary Interleukin-6 profiles in patients with periodontitis: A cross-sectional study

OBJECTIVE

The aim of this study was to analyze and identify the association among salivary interleukin-6 (IL-6) levels and periodontitis (PT) and to determine the significant trend of this association in PT patients.

STUDY DESIGN

For the present study, 49 patients with PT and 47 healthy subjects (HS) were enrolled and assessed for clinical parameters, blood samples and salivary IL-6 analyses. Clinical differences among groups were recorded and evaluated. The Spearman Correlation and the Jonckheere-Terpstra Test were applied in order to assess the interdependence between salivary IL-6 and PT.

RESULTS

Patients in the PT group had significantly higher median salivary IL-6 levels [195.4 (184.6-205.9 pg/mL)] compared to the HS group [101.9 (89.5-115.4 pg/mL) (p < 0.001). Salivary IL-6 levels were negatively correlated with C-reactive protein, with the number of teeth and with clinical attachment loss (CAL), probing pocket depth (PPD), and bleeding sites (FMBS) (p < 0.001). Furthermore, in patients with PT, salivary IL-6 levels were inversely associated (P-trend) with the number of teeth (p < 0.001), and directly associated with the proportional extent of PT (CAL, p = 0.006; PPD, p = 0.009; FMBS, p < 0.001).

CONCLUSIONS

The results of this study showed that PT patients presented significant higher salivary IL-6 levels compared to HS. Moreover, in the analyzed sample a significant p-trend among PT, tooth loss and increased salivary IL-6 levels was found.

Pueraria tuberosa: A Review on Traditional Uses, Pharmacology, and Phytochemistry

Pueraria tuberosa (Roxb. ex Willd.) DC. (Fabaceae), also known as Indian Kudzu (vidari kand), is a perennial herb distributed throughout India and other Asian countries. Traditionally, tuber and leaves of this plant have extensively been reported for nutritional and medicinal properties in Ayurveda as well as in Chinese traditional practices. The objective of the present review is to compile and update the published data on traditional uses, pharmacological potential, and phytochemistry of compounds isolated from the plant Pueraria tuberosa. P. tuberosa extracts and its purified compounds possess multiple activities such as anticancer, anticonvulsant, antidiabetic, antifertility, anti-inflammatory, antioxidant, anti-stress, antiulcerogenic, cardioprotective, hypolipidemic, hepatoprotective, immunomodulatory, nephroprotective, nootropic, neuroprotective, and wound healing. Tuber and leaf extracts of P. tuberosa contain several bioactive constituents such as puerarin, daidzein, genistein, quercetin, irisolidone, biochanin A, biochanin B, isoorientin, and mangiferin, which possess an extensive range of pharmacological activities. The extensive range of pharmacological properties of P. tuberosa provides opportunities for further investigation and presents a new approach for the treatment of ailments. Many phytochemicals have been identified and characterized from P. tuberosa; however, some of them are still unexplored, and there is no supporting data for their activities and exact mechanisms of action. Therefore, further investigations are warranted to unravel the mechanisms of action of individual constituents of this plant.

Evaluating the bio-application of biomacromolecule of lignin-carbohydrate complexes (LCC) from wheat straw in bone metabolism via ROS scavenging

Lignin-carbohydrate complexes (LCC) arebiomacromolecules that can be obtained from different biomass. Even some works have shown the LCC can efficiently scavenge the intracellular and endogenous reactive oxygen species (ROS), while little work has been carried out to investigate the potential application of LCC for ROS-related treatment in biological filed, especially for the treatment of periprosthetic osteolysis in vivo. In this work, Lignin-rich (LCC-A) and carbohydrate-rich (LCC-B) fractions in wheat straw are isolated and used as the ROS scavenger to promote osteoblast differentiation and inhibit osteoclast differentiation. The chemical composition and structures are characterized by high performance anion exchange chromatography (HPAEC) and nuclear magnetic resonance (NMR) technologies (quantitative ¹³C NMR and 2D-HSQC NMR), respectively. The results showed LCC-A possesses higher in vitro ROS-scavenging ability than LCC-B (89.8% vs 57.8%) and to inhibit osteoclast differentiation, whereas LCC-B more significantly activates cellular antioxidant activities via the KEAP1-NRF2-ARE pathway (218.5% vs 438.0% in the level of HO-1), thus promoting osteoblast differentiation in an inflammatory environment. Moreover, the therapeutic administration of LCC-A and LCC-B for Ti-particle-induced osteolytic murine calvariae showed both of them positively regulate and restore the bone metabolism, while preventing calvaria impairment. Hence, LCC from wheat straw exhibits efficient bone protective effects, suggesting it may be used as the promising ROS scavenger for clinical treatment of periprosthetic osteolysis.

Association among serum and salivary A. actinomycetemcomitans specific immunoglobulin antibodies and periodontitis

BACKGROUND

The aim of this study was to assess the association between serum and salivary Immunoglobulin (Ig) Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) specific antibodies in healthy controls (HC) and periodontitis (PT) patients. Furthermore, the objectives were to determine whether PT influenced serum A. actinomycetemcomitans specific antibodies and whether serum or salivary antibodies against A. actinomycetemcomitans IgG were mediated by serum high-sensitivity c-reactive protein (hs-CRP).

METHODS

Fifty-three patients with periodontitis and 48 HC were enrolled in the present study. Patients were regularly examined and characterized by clinical, salivary and blood samples analyses. A. actinomycetemcomitans IgA and IgG antibodies and hs-CRP were evaluated using a commercially available kit. The Spearman Correlation Test and Jonckheere-Terpstra Test were applied in order to assess the interdependence between serum A. actinomycetemcomitans IgG antibodies and clinical periodontal parameters. To evaluate the dependence of the serum and salivary A. actinomycetemcomitans IgG levels from possible confounders, univariate and multivariable linear regression analyses were performed.

RESULTS

Compared to HC, patients with PT had significantly higher IgA [serum: PT, 1.89 (1.2-2.2) EU vs HC, 1.37 (0.9-1.8) EU (p = 0.022); saliva: PT, 1.67 (1.4-2.1) EU vs HC, 1.42 (0.9-1.6) EU (p = 0.019)] and A. actinomycetemcomitans IgG levels [serum: PT, 2.96 (2.1-3.7) EU vs HC, 2.18 (1.8-2.1) EU (p < 0.001); saliva, PT, 2.19 (1.8-2.5) EU vs HC, 1.84 (1.4-2) EU (p = 0.028)]. In PT patients, serum A. actinomycetemcomitans IgG were associated with a proportional extent of PT and tooth loss (P-trend value< 0.001). The univariate regression analysis demonstrated that PT (p = 0.013) and high hs-CRP (p < 0.001) had a significant negative effect on serum and salivary A. actinomycetemcomitans IgG levels. The multivariate regression analysis showed that PT (p = 0.033), hs-CRP (p = 0.014) and BMI (p = 0.017) were significant negative predictors of serum A. actinomycetemcomitans IgG while hs-CRP (p < 0.001) and BMI (P = 0.025) were significant negative predictors of salivary A. actinomycetemcomitans IgG.

CONCLUSIONS

PT patients presented a significantly higher serum and salivary A. actinomycetemcomitans IgA and IgG compared to HC. There was a significant increase in serum A. actinomycetemcomitans IgG when patients presented a progressive extent of PT. Moreover, PT and hs-CRP were significant negative predictors of increased salivary and serum A. actinomycetemcomitans IgG levels.

TRIAL REGISTRATION

The study was retrospectively registered at clinicaltrials.gov ( NCT04417322 ).