Difference and alteration in pharmacokinetic and metabolic characteristics of low-solubility natural medicines.

Drug metabolism plays vital roles in the absorption and pharmacological activity of poorly soluble natural medicines. It is important to choose suitable delivery systems to increase the bioavailability and bioactivity of natural medicines with low solubility by regulating their metabolism and pharmacokinetics. This review investigates recent developments about the metabolic and pharmacokinetic behavior of poorly soluble natural medicines and their delivery systems. Delivery systems, dosage, administration route and drug-drug interactions alter the metabolic pathway, and bioavailability of low-solubility natural medicines to different degrees. Influencing factors such as formulation, dosage, and administration route are discussed. The metabolic reactions, metabolic enzymes, metabolites and pharmacokinetic behaviors of low-solubility natural medicines, and their delivery systems are systematically reviewed. There are various metabolic situations in the case of low-solubility natural medicines. CYP3A4 and CYP2C are the most common metabolic enzymes, and hydroxylation is the most common metabolic reaction of low solubility natural medicines. The stereo isomeric configuration can have a large influence on metabolism. This review will be useful for physicians and pharmacists to guide more accurate treatment with low-solubility natural medicines by increasing drug efficacies and protecting patients from toxic side effects.

Composite alkali polysaccharide supramolecular nanovesicles improve biocharacteristics and anti-lung cancer activity of natural phenolic drugs via oral administration.

Natural phenolic drugs have good safety and various biological activities. However, poor bioavailability and inadequate bioactivity severely limit their application. A novel composite alkali polysaccharide nanovesicle was formed with supramolecule- and nano- technologies to efficiently deliver natural phenolic antitumor drugs. Alkali polysaccharide nanovesicles (ASDLM) containing supramolecular diferuloylmethane (DLM) had the additional effects of alkali polysaccharide nanovesicles and supramolecules of drug and high-molecular-weight polymers. DLM was isolated from the external environment when double loaded by cyclodextrin and nanovesicles; The nanosize, negative/positive charges and supramolecular structure were beneficial attributes that helped to increase the bioavailability and antitumor activity; supramolecular DLM-loaded nanovesicles made of natural biodegradable excipients showed good safety. Compared to free DLM, ASDLM exhibited superior physicochemical characteristics, favorable changes in the in vitro/in vivo kinetic performance, a possible in vitro-in vivo correlation, enhanced in situ gastrointestinal absorption, increased bioavailability, and an elevated anti-lung cancer efficiency. Composite alkali polysaccharide nanovesicles conjugated with supramolecular-/nano- technology may provide a valuable platform for the oral delivery of botanical drugs to meet clinical requirements.