Houttuynia cordata Extract Ameliorates Bladder Damage and Improves Bladder Symptoms via Anti-Inflammatory Effect in Rats with Interstitial Cystitis

Analysis of Volatile Compounds from Different Parts of Houttuynia cordata Thunb

Houttuynia cordata Thunb. is a medicinal and edible plant that has been commonly used in traditional Chinese medicine since ancient times. This study used headspace solid-phase microextraction (HS-SPME) and direct injection, combined with gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS), to identify the volatile compounds in H. cordata. Extraction from different parts of the plant using different extraction techniques for the identification of volatile compounds were determined. A total of 93 volatile components were analyzed in the leaves, stems, rhizomes, and whole plant samples of H. cordata. The leaves contained more (Z)-3-hexenal, β-myrcene, (Z)-β-ocimene, and (4E,6E)-allo-ocimene; the stems contained more geranyl acetate and nerolidol; and rhizomes contained more α-pinene, β-pinene, limonene, 2-undecanone, and decanoyl acetaldehyde. Among them, the essential oil extracted by HS-SPME could produce more monoterpenes, while direct injection could obtain higher contents of aliphatic ketones, terpene esters, sesquiterpenes, and was more conducive to the extraction of 2-undecanone and decanoyl acetaldehyde.

Pharmacological Effects of Houttuynia cordata Thunb (H. cordata): A Comprehensive Review

Houttuynia cordata Thunb (H. cordata) is a rhizomatous, herbaceous, and perennial plant widely distributed in Asia. It has multiple chemical constituents, such as alkaloids, essential oils, phenolic acids, and flavonoids used against various health problems. The essential oils and flavonoids are the main components of H. cordata that play an essential role in disease treatment and traditional health care. Moreover, the leaves and stems of H. cordata have a long medicinal history in China. In addition, H. cordata is used against several health issues, such as cold, cough, fever, pneumonia, mumps, and tumors, due to its anti-inflammatory, anti-bacterial, anti-viral, anti-oxidant, and anti-tumor effects. It protects organs due to its anti-inflammatory activity. H. cordata regulates immunity by enhancing immune barriers of the oral cavity, vagina, and gastrointestinal tract, and shows broad-spectrum activity against liver, lung, breast, and colon tumors. However, there are some gaps to be filled to understand its pathways and mechanisms. Mechanisms such as its interaction with cells, cell membranes, and various drugs are important. Studies in relation to the blood–brain barrier, lipophilicity, cAMP signaling, and skin permeability, including pharmaceutical effects, will be very useful. This review includes the biological and pharmacological activities of H. cordata based on up-to-date research.

Study of the Contents of Analogues of Aristolochic Acid in Houttuynia cordata by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry

In this study, a new and simple method was established for the simultaneous determination of analogues of aristolochic acids (aristolochic acid I, aristolochic acid II, aristolactam I and aristolactam AII) in Houttuynia cordata by ultra-high performance liquid chromatography–quadrupole/time-of-flight mass spectrometry (UHPLC–Q/TOF-MS). The samples were ultrasonically extracted with methanol, purified with HC-C18, and then separated on a C18 column (75 × 2.1 mm, 2.0 μm) at 35 °C. Under the optimized conditions, aristolochic acid I (AA-I), aristolochic acid II (AA-II), aristolactam I (AL-I) and aristolactam AII (AL-AII) all showed good linear regression (not less than 0.9987). The average recoveries of the four analytes were within the range of 72.3–105.5%, with the relative standard deviations (RSDs) being ≤7.6%. The proposed method was then applied to the determination of Houttuynia cordata samples collected from different regions in China. The results showed that none of the three carcinogenic substances (aristolochic acid I, aristolochic acid II and aristolactam I) were detected in any of the 22 samples collected from 22 different regions of China, while aristolactam AII, which has not been reported to have genotoxicity, was detected in all samples. This study provides a valuable reference for the further safety assessment of Houttuynia cordata.

Houttuynia cordata Thunb: An Ethnopharmacological Review

Houttuynia cordata Thunb (H. cordata; Saururaceae) is widely distributed in Asian regions. It plays an important role in traditional health care and disease treatment, as its aboveground stems and leaves have a long medicinal history in China and are used in the treatment of pneumonia and lung abscess. In clinical treatment, it can usually be combined with other drugs to treat dysentery, cold, fever, and mumps; additionally, H. cordata is an edible plant. This review summarizes detailed information on the phytochemistry and pharmacological effects of H. cordata. By searching the keywords “H. cordata and lung”, “H. cordata and heart”, “H. cordata and liver”, and “H. cordata and inflammation” in PubMed, Web of Science and ScienceDirect, we screened out articles with high correlation in the past ten years, sorted out the research contents, disease models and research methods of the articles, and provided a new perspective on the therapeutic effects of H. cordata. A variety of its chemical constituents are characteristic of medicinal plants, the chemical constituents were isolated from H. cordata, including volatile oils, alkaloids, flavonoids, and phenolic acids. Flavonoids and volatile oils are the main active components. In pharmacological studies, H. cordata showed organ protective activity, such as reducing the release of inflammatory factors to alleviate lung injury. Moreover, H. cordata regulates immunity, enhances the immune barriers of the vagina, oral cavity, and intestinal tract, and combined with the antibacterial and antiviral activity of its extract, effectively reduces pathogen infection. Furthermore, experiments in vivo and in vitro showed significant anti-inflammatory activity, and its chemical derivatives exert potential therapeutic activity against rheumatoid arthritis. Antitumour action is also an important pharmacological activity of H. cordata, and studies have shown that H. cordata has a notable effect on lung tumour, liver tumour, colon tumour, and breast tumour. This review categorizes the biological activities of H. cordata according to modern research papers, and provides insights into disease prevention and treatment of H. cordata.

A Systematic Review of Therapeutic Approaches Used in Experimental Models of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic bladder disorder with limited therapeutic options currently available. The present review provides an extensive overview of therapeutic approaches used in in vitro, ex vivo, and in vivo experimental models of IC/BPS. Publications were identified by electronic search of three online databases. Data were extracted for study design, type of treatment, main findings, and outcome, as well as for methodological quality and the reporting of measures to avoid bias. A total of 100 full-text articles were included. The majority of identified articles evaluated therapeutic agents currently recommended to treat IC/BPS by the American Urological Association guidelines (21%) and therapeutic agents currently approved to treat other diseases (11%). More recently published articles assessed therapeutic approaches using stem cells (11%) and plant-derived agents (10%), while novel potential drug targets identified were proteinase-activated (6%) and purinergic (4%) receptors, transient receptor potential channels (3%), microRNAs (2%), and activation of the cannabinoid system (7%). Our results show that the reported methodological quality of animal studies could be substantially improved, and measures to avoid bias should be more consistently reported in order to increase the value of preclinical research in IC/BPS for potential translation to a clinical setting.