Erding formula and bioactive markers in hyperuricemia: towards rational scientific approaches for the modernization of Traditional Chinese Medicine

Introduction: Traditional Chinese Medicine (TCM) represents one of the first holistic approaches in the world to treat and prevent disease. Herbal medicine is one of the major therapeutic remedy in TCM. It often involves multi-herb therapies instead of single herb preparations. Parallel to western medicine, hundreds of herbal formulas have been made available as finished products. Currently, the use of herbal products is popular as treatment option or to complement western medicine. Indications of the herbal formulas were established by TCM terms such as heat-clearing and/or detoxifying which lack modern pharmacological meanings. It is difficult for people without relevant background to understand such terms and their implications for treatments. Furthermore, due to the quality control issues of herbal medicines which contain multiple constituents, consumers may be confronted with the risk of using unstandardized products. Hence, in this thesis, the modernization of TCM is discussed through employing scientific pharmaceutical approaches to a traditional formula, called Erding formula (EF). The aim was to investigate if a new indication, hyperuricemia, can be assigned to a heat-clearing and detoxifying formula. Our hypothesis was: Can Erding formula be used for hyperuricemia treatment and is esculetin a bioactive marker for this new indication? Methods: A hypoxanthine and potassium oxonateinduced hyperuricemic mouse model, a xyleneinduced inflammatory mouse model, and an acetic acidinduced pain model were used to investigate EF and its constituent herbs. The quantity of esculetin was measured by high-performance liquid chromatography. The therapeutic effect of esculetin was assessed using potassium oxonate induced hyperuricemic mouse model, and esculetin and its metabolites were characterized in serum via ultra-performance liquid chromatographyquadrupole time-of-flight mass spectrometry. To develop a modern dosage form, a laboratory-scale wet bead milling approach was employed to prepare esculetin nanocrystals. The formulation was further optimized by design of experiment, and an optimized formulation was then characterized for its saturation solubility and short-term stability. Results: The study showed that EF and Viola yedoensis Makino (Viola) lowered uric acid (UA) levels, while EF and all four individual herbs had antiinflammatory and analgesic activities. These findings revealed that EF was able to treat hyperuricemia and suggested that Viola was the main herb in EF on reducing UA levels. The study showed that esculetin significantly reduced UA levels and six metabolites of esculetin were identified in serum. This confirms that esculetin was absorbed and is a suitable bioactive and quality control marker for EF in hyperuricemia treatment. An esculetin-Povacoat nanocrystal formulation with a 200 nm particle size was successfully prepared. The formulation presented up to a 1.5-fold increase in saturation solubility compared to the bulk esculetin and it was stable for 180 days. Conclusion: The studies proved that Erding formula can be used for hyperuricemia treatment with esculetin as bioactive quality control marker. As well, a new nano-sized formulation of the bioactive marker, esculetin, was created. This presented the possibility to develop an innovative nanotechnological product of the active substances derived from herbal medicine. The findings facilitated a better understanding of TCM terms and concept through mechanistic scientific experiments. This study revealed a potential pathway and an idea to modernize TCM without setting aside its unique concepts. This might increase the global acceptance of TCM products. Furthermore, the TCM concept might be useful in the development of multi-component drug products

Medicina Tradicional Chinesa (MTC) representa uma das primeiras abordagens holísticas em âmbito global para tratar e prevenir doenças. A fitoterapia consiste na principal terapia na MTC. Frequentemente, envolve terapias com múltiplas ervas em vez de preparações individuais. Paralelamente à medicina ocidental, centenas de fórmulas herbais foram disponibilizadas como produtos acabados. Atualmente, o uso de produtos fitoterápicos é popular como opção de tratamento ou para complementar a medicina ocidental. As indicações das fórmulas fitoterápicas foram estabelecidas pelos termos da MTC, tais como "limpeza pelo calor e / ou desintoxicante", que não têm significados farmacológicos modernos. É difícil para a população em geral e mesmo para profissionais sem histórico relevante na área entender tais termos e suas implicações para os tratamentos. Além disso, devido às questões de controle de qualidade dos medicamentos fitoterápicos que contêm múltiplos constituintes, os pacientes podem ser confrontados com o risco de usar produtos não padronizados. Assim, nessa tese, a modernização da MTC é discutida por meio da utilização de abordagens farmacêuticas científicas para uma fórmula tradicional, denominada fórmula de Erding (FE). O objetivo foi o de investigar se uma nova indicação, a hiperuricemia, pode ser atribuída a uma fórmula desintoxicante e de compensação de calor. Nossa hipótese foi: a fórmula de Erding pode ser usada para tratamento de hiperuricemia e a esculetina é um marcador bioativo para essa nova indicação? Foi empregado modelo de camundongo hiperuricêmico induzido por hipoxantina e oxonato de potássio, outro modelo de camundongo inflamatório induzido por xileno e, adicionalmente, modelo de dor induzida por ácido acético. Esses modelos foram usados para investigar a FE e suas ervas constituintes. A quantidade de esculetina foi determinada por cromatografia líquida de alta eficiência. O efeito terapêutico da esculetina foi avaliado utilizando modelo de camundongo hiperuricêmico induzido por oxonato de potássio, e a esculetina e seus metabólitos foram caracterizados no soro por cromatografia líquida de alto desempenho - espectrometria de massa. Para desenvolver forma farmacêutica moderna, uma abordagem de moagem em escala úmida reduzida foi empregada tendo em vista a preparação de nanocristais de esculetina. A formulação foi ainda otimizada empregado planejamento experimental. Essa fórmula foi caracterizada quanto à sua solubilidade de saturação e estabilidade a curto prazo. O estudo mostrou que a FE e a Viola yedoensis Makino (Viola) reduziram os níveis de ácido úrico (AU), enquanto a FE e as quatro plantas individuais apresentaram atividades antiinflamatória e analgésica. Esses resultados revelaram que a FE foi capaz de tratar a hiperuricemia e sugeriu que a viola foi a principal erva da FE na redução dos níveis de AU. O estudo mostrou também que a esculetina reduziu significativamente os níveis de AU e os seis metabólitos da esculetina foram identificados no soro. Tal resultado confirma que a esculetina foi absorvida e pode ser usada como marcador de controle bioativo e de qualidade para FE, no tratamento da hiperuricemia. A formulação de nanocristais de esculetin-povacoat® apresentou tamanho de partícula de 200 nm. A formulação apresentou aumento de 1,5 vezes na solubilidade de saturação em comparação com a esculetina em escala micrométrica e manteve-se estável durante 180 dias. Os estudos comprovaram que a fórmula de Erding pode ser utilizada no tratamento da hiperuricemia empregando a esculetina como marcador bioativo de controle de qualidade. Além disso, foi desenvolvida formulação inovadora, em escala nanométrica, do marcador bioativo, a esculetina. Esse resultado permitiu desenvolver produto com base nanotecnológica das substâncias ativas derivadas do fitoterápico, assim comol permitiram melhor compreensão dos termos e dos conceitos da MTC por meio de experimentos científicos mecanicistas. Esse estudo revelou potencial para a modernização da MTC sem excluir seus conceitos únicos. Isso pode aumentar a aceitação global dos produtos MTC. Além disso, o conceito de MTC pode ser útil no desenvolvimento de medicamentos de múltiplos componentes

Traditional Chinese Medicine "Pill", an Ancient Dosage Form with Surprising Modern Pharmaceutical Characteristics.

Currently, the use of Traditional Chinese Medicine (TCM) for healthy living in daily practice is widely accepted across the world. However, not much attention has been paid to the particular characteristics of TCM "pills", one of the classic dosage forms in TCM. For a better understanding, this review was undertaken to provide a modern pharmaceutical overview of pills. Over many centuries, pills have been developed in different types (honeyed pill, water-honeyed pill, watered pill, pasted pill, waxed pill, concentrated pill, and dripping pill) to achieve varying intended TCM release patterns. It suggests that knowledge relating to the impact of binders and excipients on drug release from TCM pills can be traced back to before dissolution testing was invented. Therefore, although Pills may be considered as an ancient and outdated dosage form compared to current drug delivery systems, they have surprisingly modern pharmaceutical properties that is highlighted in this article. In addition, this review found that the quality control standards for TCM pill are globally substantially different. Hence, greater effort should be taken to establish an internationally harmonized and proper standard to safeguard the quality of this dosage form and to ensure the alignment with TCM use.

Are the release characteristics of Erzhi pills in line with traditional Chinese medicine theory? A quantitative study.

OBJECTIVE: Traditional Chinese medicine (TCM) has been widely used throughout China to prevent and cure diseases for thousands of years, and now it is a part of the integrative medicine field that is available in Western societies. To ensure the safety and quality of the herbal medicines that are a major part of the TCM tradition, they must be held to modern pharmaceutical standards. Erzhi pill (EZP) is a Chinese Pharmacopeia-listed herbal preparation that is used in the long-term clinical management of post-menopausal symptoms, osteoporosis and menstrual disorders. Until now, whether the drug release mechanism of EZP is in line with its intended TCM usage has not been studied. METHODS: The release of specnuezhenide from three EZPs (self-made, Leiyunshang and Renhe) in simulated gastric fluid (SGF), acetate buffer (pH 4.5 buffer) and simulated intestinal fluid (SIF) was investigated in a dissolution test. The water uptake capacity and erosion extent of the three EZPs were investigated using swelling and erosion studies. The drug release mechanism was further assessed through statistical model fitting, using DDSolver software. RESULTS: The release of specnuezhenide from all three EZPs in SGF was less than 50% within a 4 h period. However, over 70% of the specnuezhenide was released from each EZP in both pH 4.5 buffer and SIF in the same time. Analysis of the swelling and erosion behaviors and the drug release mechanism of the three EZPs confirmed that the release rate from EZP followed a sustained release profile, which was an interactive combination of swelling and erosion. CONCLUSION: This study showed that the release pattern from the pills was in line with the intended TCM use of EZP. TCM had not only theoretically considered sustained release from the pills, but also formulated them to achieve this release pattern. When establishing quality control standards for pills, the theoretical TCM usage and the actual release patterns need to be considered.

Esculetin as bioactive marker: towards a rational scientific approach for the treatment of hyperuricemia using Traditional Chinese Medicine

Traditional Chinese Herbal Medicine has been used to prevent and cure disease in China for thousands of years and has gained global interest in recent decades. The Erding formula is a Chinese Pharmacopeia (ChP)-listed herbal preparation used for treating sore throat, carbuncles and boils. Esculetin is a ChP quality control (QC) marker for these indications. A previous study found that a new indication, hyperuricemia, can be added to the Erding formula. Therefore, this study aimed to evaluate whether the traditionally used marker, esculetin, still has bioactivity for hyperuricemia, which is substantially different from the original indications. The study analyzed the quantity of esculetin by high-performance liquid chromatography, assessed the therapeutic effect of esculetin using animal model, and then characterized esculetin and its metabolites in serum via ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The results showed that the esculetin content in the aqueous Erding extract was 0.26±0.05% (w/w). Both the Erding extract and esculetin significantly reduced uric acid levels. Six metabolites of esculetin were identified in mice serum. This study revealed a rational scientific approach to prove esculetin is a reliable bioactive and QC marker for Erding formula in hyperuricemia treatment which contributed to ensure product quality and therapeutic efficacy.

Erding Formula in hyperuricaemia treatment: unfolding traditional Chinese herbal compatibility using modern pharmaceutical approaches.

OBJECTIVES: Traditional Chinese herbal formulas are difficult to be understood because of complex compositions and specific therapeutic principles. To better understand herbal compatibility in Traditional Chinese medicine (TCM), this study was conducted to investigate the effects of a Chinese pharmacopoeia-listed formula, Erding Formula (EF) and its constituent herbs for a new indication, hyperuricaemia. METHODS: A hypoxanthine and potassium oxonate-induced hyperuricemic mouse model, a xylene-induced inflammatory mouse model and an acetic acid-induced pain model were used to test the effects of EF and its constituent herbs. In addition, we investigated whether EF and/or its relevant herbs had an impact on the expression of URAT1 and OAT3 mRNA. KEY FINDINGS: The results showed EF and individual herbs had pharmacological effects on selected targets. Only Viola yedoensis Makino (Viola) lowered uric acid levels, while all four herbs had anti-inflammatory and analgesic effects. The EF may lower the uric acid level through inhibiting the expression of URAT1 mRNA and enhancing the expression of OAT3 mRNA. CONCLUSIONS: These findings provide pharmacological insights into the effects of EF and individual herbs on UA excretion. This study suggests that Viola is the main herb in EF. This study facilitates better understanding of TCM principles and theories using modern pharmaceutical approaches.