Antibiofilm and Anti‐Inflammatory Activities of Houttuynia cordata Decoction for Oral Care

Abstract

Dental biofilms that form in the oral cavity play a critical role in the pathogenesis of several infectious oral diseases, including dental caries, periodontal disease, and oral candidiasis. Houttuynia cordata (HC, Saururaceae) is a widely used traditional medicine, for both internal and external application. A decoction of dried HC leaves (dHC) has long been consumed as a health-promoting herbal tea in Japan. We have recently reported that a water solution of HC poultice ethanol extract (wHCP) exerts antimicrobial and antibiofilm effects against several important oral pathogens. It also exhibits anti-inflammatory effects on human keratinocytes. In our current study, we examined the effects of dHC on infectious oral pathogens and inflammation. Our results demonstrated that dHC exerts moderate antimicrobial effects against methicillin-resistant Staphylococcus aureus (MRSA) and other oral microorganisms. dHC also exhibited antibiofilm effects against MRSA, Fusobacterium nucleatum (involved in dental plaque formation), and Candida albicans and inhibitory effects on interleukin-8, CCL20, IP-10, and GROα productions by human oral keratinocytes stimulated by Porphyromonas gingivalis lipopolysaccharide (a cause of periodontal disease), without cytotoxic effects. This suggests that dHC exhibits multiple activities in microorganisms and host cells. dHC can be easily prepared and may be effective in preventing infectious oral diseases.

Flavones, Flavonols, and Glycosylated Derivatives—Impact on Candida albicans Growth and Virulence, Expression of CDR1 and ERG11, Cytotoxicity

“…Further insight into antibiofilm potential of quercetin has been provided in the study by Gao et al [18] where it was observed that treatment with this flavonoid leads to reduced ALS1, ALS3 (Agglutinin Like Sequence gene family), HWP1 (Hyphal Wall Protein), and SUN41 (gene encoding for secreted beta-glucosidase) expression levels. Quercitrin had the lowest potential to reduce biofilm formation among all the flavonoids tested in our study ( Figure 1) with its complete lack of activity towards C. albicans CAD1 biofilm observed previously [19]. On the other hand, excellent activity on inhibition of C. albicans biofilm formation was addressed to another flavonol glycoside, isoquercitrin (tested concentration 9.38-37.5 µg/mL) ( Figure 1) with a previous study [19] highlighting its antibiofilm potential in higher concentration-200 µg/mL.…”

“…Quercitrin had the lowest potential to reduce biofilm formation among all the flavonoids tested in our study ( Figure 1) with its complete lack of activity towards C. albicans CAD1 biofilm observed previously [19]. On the other hand, excellent activity on inhibition of C. albicans biofilm formation was addressed to another flavonol glycoside, isoquercitrin (tested concentration 9.38-37.5 µg/mL) ( Figure 1) with a previous study [19] highlighting its antibiofilm potential in higher concentration-200 µg/mL. Rutin was among the natural compounds with the lowest activity against biofilm formation in this study (Figure 1) with its lack of C. albicans CAD1 antibiofilm activity also observed earlier [19].…”

“…On the other hand, lower activity of quercetin was observed in previous studies: MIC 100 µg/mL, C. albicans ATCC 10231 [17], MIC > 83 µg/mL, clinical isolates, and C. albicans 10231 [14], and MIC 128-512 µg/mL, clinical isolates, and reference C. albicans strains ATCC 10231 and SC5314 [18]. The obtained information regarding excellent antifungal potential of the flavonol glycoside, quercitrin (MIC 37.5 µg/mL) (Table 1), differs from studies by Gehrke et al [17] and Sekita et al [19] where MICs 100 µg/mL (towards C. albicans ATCC 10231) and >512 µg/mL (C. albicans CAD1, clinical isolate), respectively, were found. Isoquercitrin in our study exhibited MIC 37.5 µg/mL (Table 1) while an earlier study [20] established much better antifungal potency with MIC 2.5 µg/mL towards C. albicans ATCC 90028.…”

Herbal Tea for the Management of Pharyngitis: Inhibition of Streptococcus pyogenes Growth and Biofilm Formation by Herbal Infusions

“…Herbal teas provide relief for pharyngeal inflammation in patients with streptococcal pharyngitis. Anti-inflammatory activities of herbal extracts and infusions have been shown by several authors previously [55,56]. Our recently published data on anti-inflammatory properties of these extracts have proven the ability of all four efficacious HWIs for suppression of pro-inflammatory cytokines released from inflamed human tonsil epithelial cells (HTonEpiCs) induced by antigens (lipoteichoic acid and peptidoglycan) of S. pyogenes [8].…”

Traditional Chinese Medicine as a Potential Source for HSV-1 Therapy by Acting on Virus or the Susceptibility of Host

“…A number of published reports over the past few years hypothesized the extracts of Houttuynia cordata to be one of the therapeutic possibilities of HSV-1 infection. H. cordata , also named “Yu-xing-cao”, is a vegetable crop and has been used widely as an effective TCM for hundreds of years due to its anti-inflammatory [ 64 , 65 ] and antiviral [ 42 , 46 , 50 ] activities.…”