Erythritol inhibits the growth of periodontal-disease-associated bacteria isolated from canine oral cavity

Evaluation of the antibacterial effect of Epigallocatechin gallate on the major pathogens of canine periodontal disease and therapeutic effects on periodontal disease mice

Background

Periodontal disease (PD) is a prevalent oral affliction in canines, with limited therapeutic options available. The potential transmission of oral bacteria from canines to humans through inter-species contact poses a risk of zoonotic infection. Epigallocatechin gallate (EGCG), the principal catechin in green tea polyphenols, exhibits antibacterial properties effective against human PD. Given the clinical parallels between canine and human PD, this study explores the feasibility of employing EGCG as a therapeutic agent for canine PD.

Methods and results

Initially, a survey and statistical analysis of bacterial infection data related to canine PD in China were conducted. Subsequently, the primary pathogenic bacteria of canine PD were isolated and cultivated, and the in vitro antibacterial efficacy of EGCG was assessed. Furthermore, verify the therapeutic effect of EGCG on a mouse PD model in vivo. The high-throughput 16S rRNA gene sequencing identified Porphyromonas, Fusobacterium, Treponema, Moraxella, and Capnocytophaga as the genera that distinguishing PD from healthy canines' gingival crevicular fluid (GCF) samples in China. The anaerobic culture and drug susceptibility testing isolated a total of 92 clinical strains, representing 22 species, from 72 canine GCF samples, including Porphyromonas gulae, Prevotella intermedia, Porphyromonas macacae, etc. The minimum inhibitory concentration (MIC) ranging of EGCG was from 0.019 to 1.25 mg/mL. Following a 7 days oral mucosal administration of medium-dose EGCG (0.625 mg/mL), the abundance of periodontal microorganisms in PD mice significantly decreased. This intervention ameliorated alveolar bone loss, reducing the average cementoenamel junction to the alveolar bone crest (CEJ-ABC) distance from 0.306 mm ± 0.050 mm to 0.161 mm ± 0.026 mm. Additionally, EGCG (0.3125 mg/mL) markedly down-regulated the expression of inflammatory factor IL-6 in the serum of PD mice.

Conclusion

Our research demonstrates the significant antibacterial effects of EGCG against the prevalent bacterium P. gulae in canine PD. Moreover, EGCG exhibits anti-inflammatory properties and proves effective in addressing bone loss in a PD mouse model. These findings collectively suggest the therapeutic potential of EGCG in the treatment of canine PD. The outcomes of this study contribute valuable data, laying the foundation for further exploration and screening of alternative antibiotic drugs to advance the management of canine PD.

Erythritol alters phosphotransferase gene expression and inhibits the in vitro growth of Staphylococcus coagulans isolated from canines with pyoderma

Staphylococcus coagulans (SC) belongs to a group of coagulase-positive staphylococci occasionally isolated from the skin lesions of dogs with pyoderma. We recently revealed that erythritol, a sugar alcohol, inhibited the growth of SC strain JCM7470. This study investigated the molecular mechanisms involved in this growth inhibition of JCM7470 by erythritol, and determine whether erythritol inhibits the growth of SC isolated from the skin of dogs with pyoderma. Comprehensive analysis of the gene expression of JCM7470 in the presence of erythritol revealed that erythritol upregulated the expression of glcB and ptsG genes, both of which encode phosphotransferase system (PTS) glucoside- and glucose-specific permease C, B, and A domains (EIICBA), respectively, associated with sugar uptake. Moreover, erythritol suppressed in vitro growth of all 27 SC strains isolated from the skin lesions of canine pyoderma, including 13 mecA gene-positive and 14 mecA gene-negative strains. Finally, the growth inhibition of the SC clinical isolates by erythritol was restored by the addition of glucose. In summary, we revealed that erythritol promotes PTS gene expression and suppresses the in vitro growth of SC clinical isolates from dogs with pyoderma. Restoration of the erythritol-induced growth inhibition by glucose suggested that glucose starvation may contribute to the growth inhibition of SC.

A water additive with pomegranate can reduce dental plaque and calculus accumulation in dogs

Oral homecare plays a major part in dental disease prevention but it can be difficult to perform and time-consuming. Furthermore, the product used can be of limited efficiency. The goal of this study was to assess the efficacy of a water additive to limit the accumulation of plaque and calculus in dogs. Forty dogs were selected and randomly allocated to one of the two groups after scaling and polishing on day 0. The control group received no oral hygiene while the second group received the water additive (Vet Aquadent® FR3SH™, Virbac) every day. After 30 days, plaque and calculus accumulations were evaluated under anesthesia. The Gingival Bleeding Index (GBI) was assessed on days 0 and 30. On day 30, the plaque and calculus indices were significantly smaller (p < 0.05) in the Aquadent group compared to the control group with median (Q1-Q3) scores of 1.22 (0.99-1.44) vs. 2.31 (1.65-3.86), respectively for plaque and 0.25 (0.15-0.42) vs. 0.33 (0.32-0.69) for calculus. Between day 0 and day 30, the GBI significantly decreased in the control group [from 0.39 (0.21-0.56) to 0.19 (0.08-0.29)] and in the Aquadent group [from 0.33 (0.18-0.47) to 0.00 (0.00-0.00)] but the decrease was significantly greater in the Aquadent group. These results show for the first time that the water additive tested can reduce dental deposit accumulation in dogs and improve gingival health. It can be recommended after a dental cleaning, especially to owners who are reluctant to provide dental care at home due to a lack of time or convenience.

Erythritol Can Inhibit the Expression of Senescence Molecules in Mouse Gingival Tissues and Human Gingival Fibroblasts

Oral aging causes conditions including periodontal disease. We investigated how the sugar alcohol erythritol, which has anti-caries effects, impacts aging periodontal tissues and gingival fibroblasts in mice and humans in vivo and in vitro. Mice were classified into three groups: control groups of six-week-old (YC) and eighteen-month-old mice (AC) and a group receiving 5% w/w erythritol water for 6 months (AE). After rearing, RNA was extracted from the gingiva, and the levels of aging-related molecules were measured using PCR. Immunostaining was performed for the aging markers p21, γH2AX, and NF-κB p65. p16, p21, γH2AX, IL-1β, and TNFα mRNA expression levels were higher in the gingiva of the AC group than in the YC group, while this enhanced expression was significantly suppressed in AE gingiva. NF-κB p65 expression was high in the AC group but was strongly suppressed in the AE group. We induced senescence in cultured human gingival fibroblasts using H2O2 and lipopolysaccharide before erythritol treatment, which reduced elevated senescence-related marker (p16, p21, SA-β-gal, IL-1β, and TNFα) expression levels. Knockdown of PFK or PGAM promoted p16 and p21 mRNA expression, but erythritol subsequently rescued pyruvate production. Overall, intraoral erythritol administration may prevent age-related oral mucosal diseases.

Fungicidal and plant growth-promoting traits of Lasiodiplodia pseudotheobromae, an endophyte from Andrographis paniculata

Introdution

Fungal endophytes are widespread and dwell inside plant cells for at least part of their life without producing any symptoms of infection. Distinct host plants may have different fungal endophyte rates and community compositions. Despite this, the endophytic fungi connected with the host plant and their hostile behaviors, remain unknown.

Methods

The objective of the current research was to isolate and identify endophytic fungal species from the root of Andrographis paniculata. The effects of fungal isolate APR5 on the mycelial growth of phytopathogens and the production of plant-promoting traits were assessed.

Results and discussion

Endophytic fungal isolate APR5 showed higher inhibitory efficacy in dual and double plate assay against the tested phytopathogenic fungi. The scanning electron microscope analysis demonstrated that the phytopathogenic fungal hyphae were coiled by endophytes which makes them shrink and disintegrate. Further, an ethyl acetate crude extract effectively suppressed the mycelium growth of Rhizoctonia solani by 75 ± 0.1% in an agar well diffusion assay. The fungal isolate APR5 was identified as Lasiodiplodia pseudotheobromae using the nuclear ribosomal DNA internal transcribed spacer (ITS) region and qualitatively evaluated for their capacity to produce plant growth-promoting hormones. Gas chromatography-mass spectrometry was implemented to acquire a preliminary understanding of the secondary metabolic profile of ethyl acetate crude extract. 1-octadecene, erythritol, niacin, oleic acid, phenol, pantolactone, phenyl ethyl alcohol, p-cresol, and tbutyl hydroquinone are the metabolites analyzed in a crude extract of APR5 isolate and are reported to have antimicrobial properties.

Molecular microbiological characteristics of gingival pockets in the periodontal diseases of dogs

Introduction

Canine periodontitis results among other factors from a disturbed balance of dental plaque microflora and an inadequate host inflammatory response to a stimulus. This investigation sought to identify microorganisms associated with canine periodontitis.

Material and Methods

Microbiological analysis was undertaken of gingival pockets in an experimental group of 36 dogs with periodontal diseases. Swabs were collected with the use of Pet Test (MIP Pharma, Berlin, Germany) from patients with gingival pockets deeper than 5 mm. Samples were aggregated and placed in separate shipping containers with the Pet Test kit.

Results

Identification was made of the most common microorganisms, e.g. Porphyromonas gingivalis, Treponema denticola and Prevotella intermedia. The red complex constituted the largest proportion of all analysed organisms (84.26%). Capnocytophaga gingivalis was isolated from 33 dogs, Peptostreptococcus micros from 32 dogs, Fusobacterium nucleatum from 29 animals and P. intermedia from 20.

Conclusion

The highest percentage of pathogens was supplied by P. gingivalis (61%). It is thought that dogs acquire them by means of cross-species transmission. The inter-study variability of results may depend not only on the method of periopathogen detection, but also on environmental factors, host immune status or genetic background. Depending on the state of periodontal disease, patients show varied microbiological profiles of the gingival pockets.