Two New Apotirucallane-Type Triterpenoids from the Pericarp of Toona sinensis and Their Ability to Reduce Oxidative Stress in Rat Glomerular Mesangial Cells Cultured under High-Glucose Conditions

Integrated network pharmacology and pharmacological investigations to discover the active compounds of Toona sinensis pericarps against diabetic nephropathy

ETHNOPHARMACOLOGICAL RELEVANCE

Toona sinensis (A. Juss.) Roem. Is a deciduous woody plant native to Eastern and Southeastern Asia. Different parts of this plant have a long history of being applied as traditional medicines to treat various diseases. The fruits have been used for antidiabetic, antidiabetic nephropathy (anti-DN), antioxidant, anti-inflammatory, and other activities.

AIM OF THE STUDY

The purpose of this study was to investigate the effects of EtOAc (PEAE) and n-BuOH extracts (PNBE) from T. sinensis pericarps (TSP) on kidney injury in high-fat and high-glucose diet (HFD)/streptozotocin (STZ)-induced DN mice by network pharmacology and pharmacological investigations, as well as to further discover active compounds that could ameliorate oxidative stress and inflammation, thereby delaying DN progression by regulating the Nrf2/NF-κB pathway in high glucose (HG)-induced glomerular mesangial cells (GMCs).

MATERIALS AND METHODS

The targets of TSP 1-16 with DN were analyzed by network pharmacology. HFD/STZ-induced DN mouse models were established to evaluate the effects of PEAE and PNBE. Six groups were divided into normal, model, PEAE100, PEAE400, PNBE100, and PNBE400 groups. Fasting blood glucose (FBG) levels, organ indices, plasma MDA, SOD, TNF-α, and IL-6 levels, as well as renal tissue Nrf2, HO-1, NF-κB, TNF-α, and TGF-β1 levels were determined, along with hematoxylin-eosin (H&E) and immunohistochemical (IHC) analysis of kidney sections. Furthermore, GMC activity screening combined with molecular docking was utilized to discover active compounds targeting HO-1, TNF-α, and IL-6. Moreover, western blotting assays were performed to validate the mechanism of Nrf2 and NF-κB in HG-induced GMCs.

RESULTS

Network pharmacology predicted that the main targets of PEAE and PNBE in the treatment of DN include IL-6, INS, TNF, ALB, GAPDH, IL-1β, TP53, EGFR, and CASP3. Additionally, major pathways include AGE-RAGE and IL-17. In vivo experiments, treatment with PEAE and PNBE effectively reduced FBG levels and organ indices, while plasma MDA, SOD, TNF-α, and IL-6 levels, renal tissue Nrf2, HO-1, NF-κB, TNF-α, and TGF-β1 levels, and renal function were significantly improved. PEAE and PNBE significantly improved glomerular and tubule injury, and inhibited the development of DN by regulating the levels of oxidative stress and inflammation-related factors. In vitro experiments, compound 11 strongly activated HO-1 and inhibited TNF-α and IL-6. The molecular docking results revealed that compound 11 exhibited a high binding affinity towards the targets HO-1, TNF-α, and IL-6 (<-6 kcal/mol). Western blotting results showed compound 11 effectively regulated Nrf2 and NF-κB p65 protein levels, and significantly improved oxidative stress damage and inflammatory responses in HG-induced GMCs.

CONCLUSION

PEAE, PNBE, and their compounds, especially compound 11, may have the potential to prevent and treat DN, and are promising natural nephroprotective agents.

The Role of Autologous Platelet Concentrates as a Local Antibiotic Delivery System: A Systematic Scoping Review

OBJECTIVES

Ongoing research has begun to develop innovative approaches to deliver local antibiotics while minimizing systemic side effects, antimicrobial resistance, and limited tissue penetration. Autologous platelet concentrates (APCs) offer promise in delivering antibiotics directly to infection sites. Despite the interest, a comprehensive evaluation of their effectiveness is lacking. Therefore, this systematic scoping review aims to collect and appraise studies regarding the efficacy of APCs in delivering antibiotics.

METHODS

A systematic electronic search of PubMed, Scopus, and Web of Science, using a combination of keywords, was conducted up to February 2024. Articles addressing the use of APCs as a local antibiotic delivery system were included.

RESULTS

A total of 13 articles, including 10 in vitro studies, 1 in vitro and clinical study, 1 ex vivo study, and 1 clinical study, were selected. Antibiotic loading capacity and release was confirmed in all studies using doxycycline, gentamicin, linezolid, vancomycin, metronidazole, and penicillin. In addition, the antibacterial effect was obtained mainly against E. coli., P. aeruginosa, S. mitis, H. influenzae, S. pneumoniae, and S. aureus.

CONCLUSIONS

The incorporation of antibiotics into APCs has been proven to facilitate the effective release of antimicrobial agents at optimal concentrations, potentially reducing the incidence of post-operative infections, substituting, or augmenting systemic antibiotic treatment while retaining APCs' inherent healing properties.

Traditional Uses, Chemical Constituents and Pharmacological Activities of the Toona sinensis Plant

Toona sinensis (A. Juss.) Roem., which is widely distributed in China, is a homologous plant resource of medicine and food. The leaves, seeds, barks, buds and pericarps of T. sinensis can be used as medicine with traditional efficacy. Due to its extensive use in traditional medicine in the ancient world, the T. sinensis plant has significant development potential. In this review, 206 compounds, including triterpenoids (1-133), sesquiterpenoids (134-135), diterpenoids (136-142), sterols (143-147), phenols (148-167), flavonoids (168-186), phenylpropanoids (187-192) and others (193-206), are isolated from the T. sinensis plant. The mass spectrum cracking laws of representative compounds (64, 128, 129, 154-156, 175, 177, 179 and 183) are reviewed, which are conducive to the discovery of novel active substances. Modern pharmacological studies have shown that T. sinensis extracts and their compounds have antidiabetic, antidiabetic nephropathy, antioxidant, anti-inflammatory, antitumor, hepatoprotective, antiviral, antibacterial, immunopotentiation and other biological activities. The traditional uses, chemical constituents, compound cracking laws and pharmacological activities of different parts of T. sinensis are reviewed, laying the foundation for improving the development and utilization of its medicinal value.

Bioactive Usual and Unusual Triterpenoids Derived from Natural Sources Used in Traditional Medicine

Triterpenoids are accessible in several terrestrial plants as well as marine organisms, including sponges, algae, fungi, and sea cucumbers are examples of marine creatures. So far, more than 20,000 natural triterpenoids have exhibited several varied bioactivities, including anticancer, antimalarial, anti-HIV, inhibit HIF-1 activation, antibacterial, chemopreventive, anti-inflammatory, antioxidant, cardioprotective, antiviral, neuroprotective, hepatoprotective, insecticidal, antidiabetic, cytotoxic. Several plants are used in folklore medicine to treat numerous ailments, and the preparation or uses of traditional practices have been scientifically validated. Although various structural diversity has been observed in the triterpenoids, this review presents the sources and uses of those triterpenoids that showed significant biological activities which could be accessible and promoted to familiar people in the form of traditional medicine or for industrial, or pharmaceutical applications.

Terpenoids from the Seeds of Toona sinensis and Their Ability to Attenuate High Glucose-Induced Oxidative Stress and Inflammation in Rat Glomerular Mesangial Cells

Toona sinensis (A. Juss.) Roem is an edible medicinal plant that belongs to the genus Toona within the Meliaceae family. It has been confirmed to display a wide variety of biological activities. During our continuous search for active constituents from the seeds of T. sinensis, two new acyclic diterpenoids (1–2), together with five known limonoid-type triterpenoids (3–7), five known apotirucallane-type triterpenoids (8–12), and three known cycloartane-type triterpenoids (13–15), were isolated and characterized. Their structures were identified based on extensive spectroscopic experiments, including nuclear magnetic resonance (NMR), high-resolution electrospray ionization mass spectra (HR-ESI-MS), and electronic circular dichroism (ECD), as well as the comparison with those reported in the literature. We compared these findings to those reported in the literature. Compounds 5, 8, and 13–14 were isolated from the genus Toona, and compounds 11 and 15 were obtained from T. sinensis for the first time. The antidiabetic nephropathy effects of isolated compounds against high glucose-induced oxidative stress and inflammation in rat glomerular mesangial cells (GMCs) were assessed in vitro. The results showed that new compounds 1 and 2 could significantly increase the levels of Nrf-2/HO-1 and reduce the levels of NF-κB, TNF-α, and IL-6 at concentrations of 30 μM. These results suggest that compounds 1 and 2 might prevent the occurrence and development of diabetic nephropathy (DN) and facilitate the research and development of new antioxidant and anti-inflammatory drugs suitable for the prevention and treatment of DN.

Cytotoxicity and polyol pathway inhibitory activities of chemical constituents isolated from the pericarp of Toona sinensis

Toona sinensis is a medicinal and edible plant that belongs to the genus Toona of family Meliaceae. Phytochemical investigations carried out on this plant, seven apotirucallane-type triterpenoids (1-7), two cycloartane-type triterpenoids (8-9), four sterols (10-13), two sesquiterpenes (14-15), four phenols (16-19), and one lignin (20) were isolated from the pericarp of T. sinensis by silica gel column and preparative middle pressure liquid chromatography. Their structures were identified by interpretation of NMR and comparison with those reported in the literature. Compounds 11-12, 15-16, and 18 were isolated from the family Meliaceae, compounds 13-14 were obtained from the genus Toona, and compound 19 was obtained from T. sinensis for the first time. Additionally, the cytotoxicity and polyol pathway (PP) inhibitory activities of active constituents were evaluated in rat glomerular mesangial cells cultured under high glucose conditions, suggesting their potential application for a PP inhibitor.