Medical News

 Breast cancer is a common malignancy in women, and multidrug resistance is one of the main reasons affecting the efficacy of chemotherapy and patient survival in breast cancer. A tumor drug resistance-associated protein, BCRP, has been reported in breast cancer drug-resistant cell lines.  Also, BCRP is a transporter, mainly responsible for the excretion of endogenous and exogenous substances outside the cell, and has a vital role in drug metabolism research. The BCRP gene of human breast cancer resistance protein (BCRP) is located in the chromosome 4q22 region. It encodes 655 amino acids, which are present in several vital organs in the body, such as the small intestine, placenta, liver, and kidney. It is essential for drug absorption, distribution, metabolism, and excretion. Drug transport proteins play a vital role in drug metabolism kinetics. According to the drug transport mode, drug transport proteins can be divided into drug uptake proteins and drug efflux proteins.  As a membe

 Isatis Radix, also known as the big blue heel, is the dried root of the plant woad or big blue-green, which can be used clinically for influenza, mumps, chickenpox, and measles.  The liver is the leading site of drug metabolism , and applying the liver microsomal model allows for metabolite analysis studies of drugs. Drug metabolite analysis has evolved rapidly to become an essential part of pharmacokinetic studies . According to a study reported on the internet, it was found that based on the systematic screening of the active antiviral ingredients of radix isatidis, straight heliotropin B was the most abundant compound among the 31 compounds isolated from the aqueous extract of radix isatidis, and compound activity testing studies showed that it had significant antiviral and antioxidant activities. Therefore, the lignan compound Gibberellin B contained in Isatidis Radix no toginseng is one of the critical active substance bases of Isatidis Radix no toginseng against viruses. Larchol

 Mass spectrometry is an essential technique for performing drug metabolite analysis , which is characterized by high detection sensitivity, a wide range of molecular masses analyzed, and a large amount of molecular structure information provided. Moreover, mass spectrometry is often used in conjunction with other analytical methods, such as chromatography and electrophoresis, which further expands the application of mass spectrometry. For example, some researchers have used ultra-high pressure liquid chromatography-time-of-flight mass spectrometry for metabolite analysis of drugs in rats to investigate the substances that exert drug effects. 1. Mass spectrometry can be used for drug metabolite analysis Drug metabolites are derived from the metabolic reactions of drugs, and the structure of metabolites is closely related to the type of metabolic reactions and the structural properties of precursor compounds. After the metabolic transformation of a drug in vivo, only some structural mod

 In drug development, many compounds often die in clinical trials because of the toxicity or safety of their metabolites, among which the active metabolites formed by drug molecules activated by human liver metabolism are more likely to be an important cause of toxicity.  In vivo or in vitro metabolite analysis of drugs can be used to determine an early stage whether a compound is toxic and suitable for further development, thus minimizing unnecessary losses. In preclinical drug metabolite analysis and metabolite structure identification to evaluate the safety of a drug metabolite, one can identify an animal species in a routine toxicology test in which adequate exposure levels of that metabolite can be formed, which is comparable to or higher than human exposure, and then study the drug toxicity in that animal species. Alternatively, if a relevant animal species cannot be identified that forms the metabolite, the metabolite can be synthesized, and further safety evaluations can be c

 Drugs are bound to plasma proteins to varying degrees in plasma, and the degree of binding can affect the drug's absorption, distribution, metabolism, and excretion in vivo, which in turn can affect the pharmacodynamic behavior of the drug. In general, after absorption into the bloodstream, only free drug reaches the site of action and produce pharmacological activity.  Equilibrium dialysis is one of the most commonly used method to determine the free concentration of medicines based on the equilibrium principle of drug binding. It is the classical method to study drug plasma protein binding rate. It has been found that the critical physiological and pharmacological functions of proteins require the participation of small drug molecules, which can promote or inhibit the protein functions through their interaction with proteins. The binding of drugs to plasma proteins can affect the biological activity of drugs. Therefore, determining the drug plasma protein binding rate is more i

 Natural products and their derivatives are essential for various drug lead compounds. Finding new drugs from active natural product skeletons and optimizing lead compounds is critical to drug development. Some chemical components of Chinese medicines are of great interest to pharmaceutical R&D workers because they may have multiple pharmacological activities .  Understanding the metabolism of natural products isolated from plants or synthesized using chemical methods in vivo can provide an individual material basis for pharmacodynamic and pharmacological studies of the drug. Rats or mice are usually used as animal models for the analysis of metabolites of compounds in vivo. Drug metabolism is one of the critical factors affecting the action of drugs. Studying the pathways and stability of drug metabolism, the enzymes and kinetic parameters involved in metabolism, and the drug interaction problems caused by metabolism are necessary to find efficient and less toxic drugs. Thus it is

 Usually, good pharmacokinetics properties are one of the criteria for judging a good or bad drug. Pharmacokinetics can explore the absorption, distribution, metabolism, and excretion of drugs in the body, as well as the pharmacological and toxicological significance, brought about in this process, to ensure the safe dose of rational clinical use of drugs, reduce the incidence of adverse reactions in the process of clinical use, and ultimately ensure the safety of human drug use. Among them, drug excretion is an essential component of drug elimination in vivo and is part of the pharmacokinetic study. Generally, drugs are excreted through the kidneys, bile, lungs, breast milk, salivary glands, bronchial glands, sweat glands, and intestines. 1、Renal The kidney is an essential organ for drug excretion. The basic structure of the kidney is the renal unit, which consists of the glomerulus and the renal tubules, and there are about one million renal units in a kidney. The blood flow through

 A large number of candidate compounds is the basis for drug development, and compound activity screening and testing are critical to obtaining candidate compounds with clinical safety data. In screening candidate compounds, pharmacokinetic parameters are another important screening metric to examine potential compounds in addition to their efficacy, which can be used to better control drug development time and reduce drug development costs by excluding candidates with suboptimal pharmacokinetic parameters early in drug development. Image from pixabay Modern advances in science and technology have greatly accelerated the rate of drug candidate discovery, with thousands of new compounds requiring screening each year. When a candidate compound enters the clinical phase, it is usually studied in healthy volunteers to obtain the kinetic parameters of the drug in humans.  A large number of candidate compounds are often eliminated for pharmacokinetic reasons. Important pharmacokinetic param