Biological and Antibacterial Activities of the Natural Herb <i>Houttuynia cordata</i> Water Extract against the Intracellular Bacterial Pathogen <i>Salmonella</i> within the RAW 264.7 Macrophage

Abstract

Houttuynia cordata has a long history of use in indigenous systems of medicine as an antiseptic, febrifuge, diuretic, and deobstruant. It is frequently used in many traditional medicines for its antimicrobial, antiviral, and antiinflammatory properties. [1][2][3][4] H. cordata contains of methyl nonyl ketone, caryophyllene, bornyl acetate, a-pinene, b-pinene, limonene, and other components. These components have antibacterial properties against the Gram-positive bacteria Staphylococcus aureus and Sarcina ureae. 5) In experimental studies, H. cordata exhibited antibacterial activity, antileukemic activity, antiinflammatory activity, anaphylactic reaction and mast cell activation, and modulated nitric oxide (NO) production. [6][7][8][9][10] However, to date, studies to understand the other antibacterial effects, including the intracellularly replicating pathogens of these plants, are lacking.The mammalian immune response is divided broadly into the innate and adaptive responses. Innate immune responses of mammals involve the first line of defense against invading microorganisms, including the release of antimicrobial peptides at epithelial surfaces, phagocytosis, and intracellular killing of microorganisms by phagocytes and the activation of the complement cascade. In contrast, the adaptive immune response is antigen specific and modified by previous antigen exposure. 11) In the innate immune response, the reactive oxygen intermediates (ROIs) such as superoxide and reactive nitrogen intermediates (RNIs) such as NO have a key role in intracellular killing of microorganisms within phagocytes. 12)Several studies reported that RNIs are important for controlling Salmonella multiplication within macrophages. 13,14)Salmonellosis is a major bacterial zoonosis that causes a variety of disease syndromes, from self-limiting enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans.15) The etiologic agents of salmonellosis are Salmonella sp. characterized by motile, Gram-negative, rod-shaped bacteria and facultative intracellular pathogens that can multiply within professional and nonprofessional phagocytes. Recently, the emergence of multidrugresistant strains of Salmonella sp. has caused more serious problems in public health.16) Multidrug resistance is a worldwide problem that does not recognize international borders and can indiscriminately affect the treatment and prevention of various diseases.To kill intracellular bacteria including Salmonella sp., Brucella sp., Listeria sp., Shigella sp., etc., much effort is needed to develop antibiotics, determine treatment duration, and resolve other issues.In this study, we examined the antibacterial effects, and macrophage activation of H. cordata water extract (HCWE) such as morphologic changes, NO production, phagocytic activity, and effects against the Salmonella enterica serovar Typhimurium in vitro and in vivo. Salmonellosis is a major bacterial zoonosis that causes a variety of disease syndromes, from self-limiting enteritis to fatal infec...

A Salmonella enterica serovar Typhi plasmid induces rapid and massive apoptosis in infected macrophages

“…A few recent studies have shed some light on the basis for the cytotoxic effect of Salmonella on murine macrophage cells. 11,21 These reports demonstrate that many Salmonella serovars can trigger cytotoxicity in murine macrophages and that apoptosis is responsible for some of the observed overall host cell death. Furthermore, apoptosis requires a functional Salmonella type III secretion system and actively replicating Salmonella.…”

Coptidis rhizome and Si Jun Zi Tang Can Prevent Salmonella enterica Serovar Typhimurium Infection in Mice

“…It has been demonstrated that a methanol extract of CR, Mume fructus , and Scutellariae radix combination, offered an alternative way to treat S. Gallinarum infection in chickens [12]. The aqueous extract of Houttuyniae herba has been shown to inhibit S. Typhimurium growth and its invasion of macrophages; it can also significantly increase the survival time of infected mice [13]. Many TCM formulas have been widely used for improving gastrointestinal dysfunction and modifying the immune response to inflammation, such as Ger Gen Chyn Lian Tang and Huoh Shiang Jeng Chih San, which have shown curative effects in treating infectious diseases [14], [15].…”

Water Extract of Houttuynia cordata Thunb. Leaves Exerts Anti-Obesity Effects by Inhibiting Fatty Acid and Glycerol Absorption

“…(9)(10)(11). Thus far, the extracts and components of H. cordata have been demonstrated to exhibit antioxidative, antiviral, antibacterial, antihypertensive and anti-inflammatory effects (12)(13)(14)(15)(16)(17). However, these extracts have not yet been reported to have anti-obesity effects.…”