Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and its prevalence is still growing rapidly. However, the efficient therapies for this kidney disease are still limited. The pathogenesis of DKD involves glucotoxicity, lipotoxicity, inflammation, oxidative stress, and renal fibrosis. Glucotoxicity and lipotoxicity can cause oxidative stress, which can lead to inflammation and aggravate renal fibrosis. In this review, we have focused on in vitro and in vivo experiments to investigate the mechanistic pathways by which natural compounds exert their effects against the progression of DKD. The accumulated and collected data revealed that some natural compounds could regulate inflammation, oxidative stress, renal fibrosis, and activate autophagy, thereby protecting the kidney. The main pathways targeted by these reviewed compounds include the Nrf2 signaling pathway, NF-κB signaling pathway, TGF-β signaling pathway, NLRP3 inflammasome, autophagy, glycolipid metabolism and ER stress. This review presented an updated overview of the potential benefits of these natural compounds for the prevention and treatment of DKD progression, aimed to provide new potential therapeutic lead compounds and references for the innovative drug development and clinical treatment of DKD.

Natural products play an important role in drug discovery. This work employed a natural product 1-methylhydantoin as the lead compound to develop novel dual-active drugs. 1-Methylhydantoin was isolated from Oviductus Ranae, which is a traditional Chinese medicine that has been used for tussive and inflammation treatment for a long time. An in silico study screened the more active 1-methylhydantoin derivatives. Antitussive assessment indicated that the newly synthesized agent had similar bioactivity with the natural product. An anti-inflammatory model used xylene induced ear edema model. At the same dosage (100 mg/Kg), the newly prepared agent had an inhibition rate 53.18% which was much higher than that of the lead compound (22.69%). The results might be ascribed to the cyclooxygenases-1 (COX-1) and cyclooxygenases-2 (COX-2) selectivity, and the fitness of the compound, and the binding pocket. The anti-particulate matter (PM 2.5) acute pneumonia was evaluated through an in vivo model constructed by nasal instillation with PM 2.5 suspension. The results of the above models suggested that this novel agent had remarkable antitussive, anti-inflammatory, and anti-PM 2.5 acute pneumonia activities.

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, and its incidence continues to increase each year. Yet, there is still no definitive drug that can stop its development. This review focuses mainly on lipotoxicity, oxidative stress, inflammation, and intestinal flora dysbiosis to understand NAFLD’s pathogenesis. In this review, we used NCBI’s PubMed database for retrieval, integrating in vivo and in vitro experiments to reveal the therapeutic effects of natural compounds on NAFLD. We also reviewed the mechanisms by which the results of these experiments suggest that these compounds can protect the liver from damage by modulating inflammation, reducing oxidative stress, decreasing insulin resistance and lipid accumulation in the liver, and interacting with the intestinal microflora. The natural compounds discussed in these papers target a variety of pathways, such as the AMPK pathway and the TGF-β pathway, and have significant therapeutic effects. This review aims to provide new possible therapeutic lead compounds and references for the development of novel medications and the clinical treatment of NAFLD. It offers fresh perspectives on the development of natural compounds in preventing and treating NAFLD.

The effective components of Coptis chinensis were extracted by ultrasound-assisted technology, and the contents of palmatine and berberine were used as indexes by using Coptis chinensis as raw material and eutectic solvent as extractant. In addition, the effects of hydrogen bond donor type, molar ratio of hydrogen bond donor to acceptor, material-liquid ratio, water content of eutectic solvent system, sonication time, power, and ultrasonic temperature on the extraction rate of palmatine and berberine were studied. The optimum extraction technology of palmatine and berberine from Coptis chinensis was determined by single-factor experiment and response surface optimization test. As a result, it showed that the eutectic solvent system was constructed with choline chloride as hydrogen bond acceptor and phenol as hydrogen bond donor, with a molar ratio of 1:3. In addition, water content of the eutectic solvent system was 30, ratio of material to liquid was 30g/mL, ultrasonic time was 30min, ultrasonic power was 200W, and ultrasonic temperature was 60°C. At this time, the contents of palmatine and berberine in Coptis chinensis were 16.7145mg/g and 57.4013mg/g, respectively, which were predicted to be the same as the value, and the extraction effect was better than that of traditional extraction solvent method.

Taking Phellodendron chinense Schneid (PcS) as the raw material with ultrasonic‐assisted eutectic solvent, the effects of various DESs on the extractable content of palmatine and berberine in PcS were investigated. On the basis of the single‐factor test, the best DES was determined to be choline chloride and 1,3‐propanediol (mole ratio 1 : 2). After optimizing by the response surface method, the optimum extraction conditions were as follows: the solid‐liquid ratio was 1 : 30 (w/v), water content was 30% (v/v), vortex time was 7 min, ultrasonic time was 20 min, ultrasonic temperature was 60°C, ultrasonic power was 400 W, and the content of palmatine in PcS was 5.421 ± 0.283 mg/g, and the content of berberine in PcS was 15.573 ± 0.539 mg/g. Therefore, DES prepared from choline chloride and 1,3‐propanediol can be used to extract palmatine and berberine from PcS. The optimized process conditions determined by the response surface method are reliable and can provide a reference for the green extraction of effective components from PcS.

In this paper, ultrasonic-assisted deep eutectic solvent (DES) extraction was applied to the acquisition of chromones (cimicifugin, prim-o-glucosylcimifugin, and 5-o-methylvisamminoside) from Saposhnikoviae radix (SR). The extraction effects of 11 prepared DESs were screened taking contents of chromones as indexes. Furthermore, the optimum extraction conditions were confirmed using a single-factor test and response surface optimization test. Scavenging activities of DPPH anion and ABTS cation radicals of different SR extracts (DES, methanol, and ethanol) were studied. The analysis results of best extraction conditions optimized by Design-Expert software were as follows: extraction time (40min), extraction temperature (60°C), and the solid/liquid ratio (32mL/g). Scavenging rates of the DES extract for DPPH anion radical and ABTS cation radical were found to be 75.31 and 65.71, which were higher than those of methanol and ethanol extracts. In conclusion, the developed extraction method can be regarded as a safe, green, and more effective approach for the extraction of chromones in SR.