Anti-hyperuricemic bioactivity of Alstonia scholaris and its bioactive triterpenoids in vivo and in vitro

Phytochemical compounds for treating hyperuricemia associated with gout: a systematic review

Gout is a prevalent metabolic disorder characterized by increased uric acid (UA) synthesis or decreased UA clearance from the bloodstream, leading to the formation of urate crystals in joints and surrounding tissues. Hyperuricemia (HUA), the underlying cause of gout, poses a growing challenge for healthcare systems in developed and developing countries. Currently, the most common therapeutic approaches for gouty HUA primarily involve the use of allopathic or modern medicine. However, these treatments are often accompanied by adverse effects and may not be universally effective for all patients. Therefore, this systematic review aims to provide a comprehensive outline of phytochemical compounds that have emerged as alternative treatments for HUA associated with gout and to examine their specific mechanisms of action. A systematic search was conducted to identify phytochemicals that have previously been evaluated for their effectiveness in reducing HUA. From a review of > 800 published articles, 100 studies reporting on 50 phytochemicals associated with the management of HUA and gout were selected for analysis. Experimental models were used to investigate the effects of these phytochemicals, many of which exhibited multiple mechanisms beneficial for managing HUA. This review offers valuable insights for identifying and developing novel compounds that are safer and more effective for treating HUA associated with gout.

Alstonia scholaris (L.) R. Br. ameliorated diabetic nephropathy through PPAR-δ pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Alstonia scholaris was utilized as a medicinal herb for the management of diabetes traditionally, with diabetic nephropathy (DN) was one of its major complications. However, the effect of A. scholaris on DN have yet to be explored.

AIM OF THE STUDY

To investigate the effect and mechanism of A. scholaris in treating DN.

MATERIALS AND METHODS

The high glucose (HG)-induced renal podocyte (MPC5) injury model was conducted in vitro, and DN mice induced by high fat diet and combined with streptozotocin (HFD + STZ) was employed to evaluate bioactivity in vivo. Transcriptome analysis was conducted to explore the potential targets of vallesamine, with findings further validated by RT-qPCR and WB analysis. Furthermore, the binding affinity of vallesamine to its potential target was investigated through molecular docking and dynamics simulation.

RESULTS

Four major alkaloids of A. scholaris demonstrated significant efficacy in mitigating HG-induced MPC5 cell damage, and they also restored oxidation balance while reducing the release of nitric oxide and lactate dehydrogenase. Oral administration of the total alkaloids and the four compounds for 6 weeks, respectively, could ameliorate proteinuria, urinary protein-to-creatinine ratio, hyperglycemia and hyperlipidemia significantly, and as well elevate serum levels of total protein and albumin concurrently in HFD + STZ induced mice. Moreover, renal injury and matrix hyperplasia were also improved after the treatment. Notably, vallesamine (5 mg/kg) exerted a pronounced effect on DN through upregulating Ppar-δ, Fads2, Me1, Ehhadh, Lpl, Scd1, Acsl1, and downregulating Hmgcs5, Slc27a1, Dbil5 and Plin5 gene expressions of PPAR pathway. Meanwhile, proteins related to lipid metabolism (PPAR-δ and ACSL1, HMGCS2) as well as the associated with renal inflammation (PODOCIN, BCL-2, and IL-6) were regulated by vallesamine intervention. In addition, vallesamine-PPAR-δ complexes maintained structural integrity, with the binding free energy of -25.84 kJ/mol, indicating a particularly high affinity between the ligand and the receptor in molecular dynamics and docking.

CONCLUSION

Total alkaloids from A. scholaris and its main components vallesamine alleviated kidney injury induced by HFD + STZ through modulation the PPAR-δ pathway, providing a potential strategy for the development of new botanical drug to treat DN.

Targeting purine metabolism-related enzymes for therapeutic intervention: A review from molecular mechanism to therapeutic breakthrough

Purines are ancient metabolites with established and emerging metabolic and non-metabolic signaling attributes. The expression of purine metabolism-related genes is frequently activated in human malignancies, correlating with increased cancer aggressiveness and chemoresistance. Importantly, under certain stimulating conditions, the purine biosynthetic enzymes can assemble into a metabolon called "purinosomes" to enhance purine flux. Current evidence suggests that purine flux is regulated by a complex circuit that encompasses transcriptional, post-translational, metabolic, and association-dependent regulatory mechanisms. Furthermore, purines within the tumor microenvironment modulate cancer immunity through signaling mediated by purinergic receptors. The deregulation of purine metabolism has significant metabolic consequences, particularly hyperuricemia. Herbal-based therapeutics have emerged as valuable pharmacological interventions for the treatment of hyperuricemia by inhibiting the activity of hepatic XOD, modulating the expression of renal urate transporters, and suppressing inflammatory responses. This review summarizes recent advancements in the understanding of purine metabolism in clinically relevant malignancies and metabolic disorders. Additionally, we discuss the role of herbal interventions and the interaction between the host and gut microbiota in the regulation of purine homeostasis. This information will fuel the innovation of therapeutic strategies that target the disease-associated rewiring of purine metabolism for therapeutic applications.

Undescribed indole lactones from Alstonia scholaris protecting hepatic cell damage

Six previously undescribed rigidly monoterpenoid indole alkaloids, alstolactines F-K (1-6), were isolated from Alstonia scholaris. Among them, a pair of cage-like epimers, 1 and 2, featuring a rare 6/5/6/6/7 ring system, represent the first example of C5→C20-olide, while compound 3 possesses unique degraded C18 and C19. The structures of the isolates were established by multiple spectroscopic analyses, quantum computational chemistry methods, and X-ray diffraction. Furthermore, the expression levels of proteins including NLRP3, TLR4, P-p65, NF-ĸB, Notch-2, IL-18, P-p38, and p38 in LPS-induced human normal hepatocyte (LO2) cells could be significantly downregulated by compounds 1-6, which showed potent anti-inflammatory bioactivity.

New Lupanes from Alstonia scholaris Reducing Uric Acid Level

Twelve lupanes including three new compounds named alstoscholarilups A-C (1: -3: ) were isolated from the leaves of Alstonia scholaris. Their structures were elucidated by spectroscopic analysis and ECD calculation. Structurally, compound 1: with a rare A ring-seco skeleton formed lactone and degraded C-3, while 2: with a 28-nor and 3: with a 29-nor-lupane skeleton supported the phytochemical diversity and novelty of the plant. Pharmacologically, compounds 4, 7: , and 10: reduced the serum uric acid (UA) levels of mice significantly.

Pharmacological investigation of indole alkaloids from Alstonia scholaris against chronic glomerulonephritis

BACKGROUND

As one of the most commonly used folk medicines in "Dai" ethno-medicine system, Alstonia scholaris (l.) R. Br. has also been used for treat "water related diseases", such as chronic kidney disease. However, few study was reported for it on the intervention of chronic glomerulonephritis (CGN).

PURPOSE

To investigate the effect and potential mechanism of indole alkaloids from A. scholaris leaves in ICR mice with adriamycin nephropathy, as well as providing experimental evidence for the further application.

METHODS

ICR Mice were selected for injections of adriamycin (ADR) to induce the CGN model and administered total alkaloids (TA) and four main alkaloids continuously for 42 and 28 days, respectively. The pharmacological effects were indicated by serum, urine, and renal pathological observations. The targets and pathways of indole alkaloids on CGN intervention were predicted using the network pharmacology approach, and the immortalized mice glomerular podocyte (MPC5) cells model stimulated by ADR was subsequently selected to further verify this by western blotting and RT-qPCR methods.

RESULTS

TA and four major compounds dramatically reduced the levels of urinary protein, serum urea nitrogen (BUN), and creatinine (CRE) in ADR - induced CGN mice, while increasing serum albumin (ALB) and total protein (TP) levels as well as ameliorating kidney damage. Moreover, four alkaloids effected on 33 major target proteins and 153 pathways in the CGN, among which, PI3K-Akt as the main pathway, an important pathway for kidney protection by network pharmacology prediction, and then the four target proteins - HRAS, CDK2, HSP90AA1, and KDR were screened. As a result, Val-and Epi can exert a protective effect on ADR-stimulated MPC5 cells injury at a concentration of 50 μM. Furthermore, the proteins and RNA expression of HRAS, HSP90AA1, and KDR were down-regulated, and CDK2 was up-regulated after the intervention of Val-and Epi, which were supported by Western blotting and RT-qPCR. Additionally, Val-and Epi inhibited ROS production in the MPC5 cells model.

CONCLUSION

This study is the first to confirm the potential therapeutic effect of alkaloids from A. scholaris on CGN. TA with major bioactive components (vallesamine and 19‑epi-scholaricine) could exert protective effects against the ADR-induced CGN by regulating four key proteins: HRAS, CDK2, HSP90AA1, and KDR of the PI3K-Akt pathway.

Bioactive Compounds and Their Derivatives: An Insight into Prospective Phytotherapeutic Approach against Alzheimer's Disease

Alzheimer's disease (AD) is a common neurodegenerative brain disorder that causes cellular response alterations, such as impaired cholinergic mechanism, amyloid-beta (Aβ) AD aggregation, neuroinflammation, and several other pathways. AD is still the most prevalent form of dementia and affects many individuals across the globe. The exact cause of the disorder is obscure. There are yet no effective medications for halting, preventing, or curing AD's progress. Plenty of natural products are isolated from several sources and analyzed in preclinical and clinical settings for neuroprotective effects in preventing and treating AD. In addition, natural products and their derivatives have been promising in treating and preventing AD. Natural bioactive compounds play an active modulatory role in the pathological molecular mechanisms of AD development. This review focuses on natural products from plant sources and their derivatives that have demonstrated neuroprotective activities and maybe promising to treat and prevent AD. In addition, this article summarizes the literature pertaining to natural products as agents in the treatment of AD. Rapid metabolism, nonspecific targeting, low solubility, lack of BBB permeability, and limited bioavailability are shortcomings of most bioactive molecules in treating AD. We can use nanotechnology and nanocarriers based on different types of approaches.