Pharmacology of oleanolic acid and ursolic acid

Oleanolic acid derivative OA17 inhibits trophoblast apoptosis by suppressing HIF-1α nuclear translocation in SLE-associated adverse pregnancy outcomes

BACKGROUND

Systemic lupus erythematosus (SLE) primarily affects women of reproductive age and is associated with a high incidence of adverse pregnancy outcomes (APOs). Recent studies reveal that elevated HIF-1α expression in the placenta is involved in SLE-associated APOs and multiple pregnancy complications, but no clinically approved HIF-1α inhibitors exist to mitigate APOs. OA17, a pentacyclic triterpenoid derived from structural modification of oleanolic acid (OA), exhibits potent anti-inflammatory and antioxidant properties. However, OA17 function and the underlying mechanisms in SLE pregnancy outcomes remain unclear.

PURPOSE

The aim of this study was to explore the role of HIF-1α in SLE-associated APOs and to assess the therapeutic potential of OA17 as a novel treatment.

METHODS

Human placental samples and relevant clinical data were collected from participants to explore the mechanisms SLE-associated APOs. Additionally, HTR-8/SVneocells, an Extravillous trophoblast (EVT)-immortalized cell line, were subjected to hypoxia (1 % O₂) and chemicals known to stabilize HIF-1α (CoCl2 and DMOG) to mimic the upregulation of HIF-1α observed in SLE pregnancies. The relationship between HIF-1α and oxidative stress/apoptosis in the HTR-8/SVneo cells was explored through H2O2 stimulation, sh-HIF-1α, and CUT-TAG assay. Additionally, HTR-8/SVneo was treated with OA17 and pregnant MRL-lpr mice received continuous OA17 over two weeks.

RESULTS

We demonstrated that significantly increased levels of HIF-1α and heightened apoptosis in EVT cells within the placental tissues of SLE pregnancies. Mechanistically, HIF-1α bound to the SOD2 promoter to repress SOD2 transcription and regulate ROS to promote apoptosis. OA17 treatment in lupus-prone MRL/lpr mice alleviated renal injury, reduced oxidative stress and hypoxia-induced apoptosis in EVT cells by inhibiting HIF-1α nuclear translocation, thus improving APOs. In addition, OA17 treatment attenuated the biological functions of hypoxia-impaired EVT cells, including cell proliferation, invasion, and migration.

CONCLUSION

Our data suggest that elevated HIF-1α during SLE pregnancies can be considered a contributing factor to APOs, OA17 inhibits trophoblast apoptosis by suppressing HIF-1α nuclear translocation in SLE-associated APOs. OA17 could be a potential new drug for other pregnancy complications in the clinic.

Harnessing the Power of Natural Products for Targeted Protein Degradation

Natural products have garnered significant attention due to their complex chemical structures and remarkable pharmacological activities. With inherent recognition capabilities for protein surfaces, natural products serve as ideal candidates for designing proteolysis-targeting chimeras (PROTACs). The utilization of natural products in PROTAC development offers distinct advantages, including their rich chemical diversity, multitarget activities, and sustainable sourcing. This comprehensive review explores the vast potential of harnessing natural products in PROTAC research. Moreover, the review discusses the application of natural degradant technology, which involves utilizing natural product-based compounds to selectively degrade disease-causing proteins, as well as the implementation of computer-aided drug design (CADD) technology in identifying suitable targets for degradation within the realm of natural products. By harnessing the power of natural products and leveraging computational tools, PROTACs derived from natural products have the potential to revolutionize drug discovery and provide innovative therapeutic interventions for various diseases.

Oleanolic acid inhibits appetite through the TGR5/cAMP signaling pathway

Inhibition of appetite is an effective approach to fight obesity. Recently, bile acids have been reported to suppress appetite and alleviate obesity via the Takeda G protein-coupled receptor 5 (TGR5). However, whether the downstream signaling molecule cyclic adenosine monophosphate (cAMP) of TGR5 is involved in this process remains unclear. Oleanolic acid (OA) is a plant analogue of bile acids. The study aimed to explore the effect of dietary OA supplementation on appetite and to examine the role of TGR5/cAMP signaling in this process. In our study, mice were divided into four treatment groups: basal diet, 50mg/kg OA-supplemented diet, 100mg/kg OA-supplemented diet, and 30mg/kg tauroursodeoxycholic acid (TUDCA)-supplemented diet. Our results showed that dietary supplementation of OA and TUDCA both suppressed appetite. Additionally, OA and TUDCA downregulated the expression of appetite-stimulating factors while upregulating appetite-suppressing factors in the hypothalamus. Furthermore, OA was found to activate TGR5 signaling in the hypothalamus. Mechanistic studies using N38 cells revealed that OA reduced the expression and secretion of agouti-related peptide (AgRP), while inhibition of TGR5 and cAMP attenuated this effect of OA. In conclusion, our findings suggest that OA may suppress appetite through activation of the TGR5/cAMP signaling pathway in the hypothalamus.

Nanotherapy targeting anti-aging skin cells: harnessing ursolic acid from Ocimum sanctum Linn for precision skin rejuvenation - a molecular perspective

The necessity of this work lies in the innovative application of nanotherapy to target anti-ageing skin cells, utilising ursolic acid from Ocimum sanctum Linn for precise and effective skin rejuvenation at a molecular level. Ursolic acid (UA), a pentacyclic triterpenoid compound, found in abundance in the plant O. sanctum Linn, has long been recognised for its potential anti-inflammatory, antioxidant, and anti-ageing properties. Despite its promising benefits, the direct application of UA in skincare has been limited, primarily due to its low aqueous solubility and poor skin penetration. This study explores a groundbreaking molecular approach, employing nanotechnology to enhance the delivery of UA, targeting skin cells for effective anti-ageing treatment. Through a comprehensive investigation, UA was encapsulated into biocompatible nanocarriers, ensuring increased stability, improved dermal penetration, and sustained release of the compound at the targeted site. By harnessing the specificity and efficiency of nanodelivery systems, the study achieved significant improvement in the absorption of UA in the deeper layers of the skin. This targeted intervention at the cellular and molecular level paved the way for maximising the potential of UA as an anti-ageing agent. In conclusion, the nanotherapeutic delivery of UA from O. sanctum Linn offers a paradigm shift in skincare, bringing forth a promising molecular strategy to combat skin ageing. With further advancements, this approach has the potential to revolutionise anti-ageing treatments, integrating traditional botanical wisdom with cutting-edge nanotechnology.

A 13-week repeated oral dose toxicity evaluation and a 4-week recovery evaluation of rosemary concentrate containing 50% ursolic acid in male and female rats

This study was performed to evaluate the safety of rosemary concentrate containing 50% ursolic acid (RCUA50), the ethanolic extract of rosemary. RCUA50 was administered orally for 13 weeks at 1000, 2000, and 4000 mg/kg/day, and then the rats were maintained for 4 weeks without RCUA50 administration for recovery evaluation. We observed clinical signs, body weights, food consumption, functional observations, ophthalmological examination, urinalysis, estrus cycle, hematology, clinical chemistry, sperm analysis, organ weights, gross examination, and histopathological examinations. During the dosing and recovery period, there were no test substance-related deaths, clinical signs, changes in body weights, and food consumption in all treated groups. In the main group, there were no test substance-related effects in functional observations and ophthalmological examination. In the main and recovery groups, there were no test substance-related effects in hematology, clinical chemistry, sperm analysis, organ weights, necropsy and histopathological examination. In conclusion, the repeated oral administration of RCUA50 for 13 weeks resulted in no test substance-related adverse effect at all dose levels. Therefore, the NOAEL was considered to be greater than 4000 mg/kg/day in both sexes under the conditions of this study.

Ursolic acid- betulinic acid-CCM NPs: A delivery system for improving the stability and bioavailability of CCM

The research constructed a co-assembly nanoparticles (NPs) of ursolic acid (UA) and betulinic acid (BA) as carriers to load the active substance curcumin (CCM) by co-precipitation method, aiming to improve the stability and bioavailability of CCM in the human body and enabling CCM to play more functions in the production of functional foods. The average particle size of UA-BA-CCM NPs was 222.6 nm and zeta potential was -26.63 mV. The UA-BA-CCM NPs had small size and great stability. The drug loading was up to 20.42 %. Moreover, the hydrogen bonds and π-π stacking existed in the three molecules. The result was verified by Molecular Dynamics Simulation, FITR, and UV experiments. In simulated in vitro release experiments, the release rate of the NPs was lower than free CCM in gastric phase, improving CCM bioavailability. Meanwhile, the UA-BA-CCM NPs performed better clearing free radicals than free CCM. Thus, UA-BA-CCM NPs delivery system not only could improve stability and bioavailability of CCM, but also might make CCM play a role in the functional food.

Triterpenoids from Frankincense and Boswellia: A focus on their pharmacology and 13C-NMR assignments

Here we report for the first time the entire 13C-NMR spectral assignments of 119 (out of 127) triterpenoids from the oleo-gum resins of the medicinally important genus Boswellia, which includes the culturally highly valuable Frankincense species. The complete 13C-NMR resonances of these triterpenoids isolated between 1998 and 2024 and their biological activities are presented. 13C-NMR spectroscopy is a highly powerful tool for the characterization of these bioactive natural products. The compounds are arranged according to their skeletons, i.e., ursane, oleanane, lupane, dammarane, and tirucallane triterpenes. This review will be a future reference for the identification of these compounds, which have key medicinal properties in the areas of cytotoxicity and inflammation.

Anti-Inflammatory Activity of the Major Triterpenic Acids of Chios Mastic Gum and Their Semi-Synthetic Analogues

24Z-Masticadienonic acid (MNA) and 24Z-isomasticadienonic acid (IMNA) are the major triterpenic acids in Chios Mastic Gum (CMG), a resin derived from Pistacia lentiscus var. Chia. Despite their promising pharmacological potential, limited information is available due to the complexity of isolating them in pure form. This study developed a chemo-selective method for isolating MNA and IMNA and investigated their chemical transformation through isomerization of the external double bond and A-ring contraction of the triterpene scaffold. A rapid method for isolating MNA from CMG was first established, followed by a high-yield acid-catalyzed procedure to obtain both 24Z and 24E isomers of IMNA. Additionally, a basic catalyzed isomerization of IMNA led to the formation of two new compounds with A-ring contraction, which could serve as novel scaffolds for the design of new triterpene analogs. The mixture of MNA/IMNA, along with the individual compounds and their semi-synthetic analogs, exhibited significant anti-inflammatory activity. Notably, 24E-isomasticadienonic acid and 24Z-2-hydroxy-3-oxotirucalla-1,8,24-trien-26-oic acid, a previously unreported compound, significantly reduced the mRNA expression levels of Tnf, Il6, and Nfkb1 in RAW 264.7 macrophage cells.

Anti-cariogenic effect of experimental resin cement containing ursolic acid using dental microcosm biofilm

OBJECTIVE

This study aimed to assess the anticariogenic effects of resin cement containing varying ursolic acid (UA) concentrations and to determine the optimal UA concentrations in the microcosm biofilm model.

MATERIALS AND METHODS

Experimental resin cements with UA concentrations of 0, 0.1, 0.5, 1.0, and 2.0 wt% were prepared. Class I cavities were prepared on 50 extracted human molars and restored with composite inlays and experimental resin cements. Tooth samples were subjected to artificial caries induction for 10 days in a microcosm biofilm model using human saliva as an inoculum, and then mineral changes were evaluated using quantitative light-induced fluorescence (ΔF and ΔQ) and micro-computed tomography (CT). The bacterial composition of the human saliva was analyzed by 16 s RNA microbiome profiling. One-way analysis of variance with Tukey and Duncan post-hoc tests was employed for statistical analysis (p < 0.05).

RESULTS

As the UA concentration increased, resin cement decreased ΔF and ΔQ before and after caries induction but showed a significant difference only in ΔQ at UA concentration ≥ 1.0 % (p < 0.05). The gray value analysis result of micro CT also showed a significant difference at UA concentration ≥ 1.0 % (p < 0.05). In the human saliva analysis, bacterial composition remained within normal oral microbiota ranges.

CONCLUSION

Resin cements containing at least 1.0 % of UA exhibited an anticariogenic effect on dental microcosm biofilms.

CLINICAL RELEVANCE

To reduce the failure of restorations, it is essential to prevent the occurrence of secondary caries. The application of UA in resin cement can be utilized to prevent the formation of secondary caries due to the anticariogenic effect of UA.

Repositioning of anti-infective compounds against monkeypox virus core cysteine proteinase: a molecular dynamics study

Monkeypox virus (MPXV) core cysteine proteinase (CCP) is one of the major drug targets used to examine the inhibitory action of chemical moieties. In this study, an in silico technique was applied to screen 1395 anti-infective compounds to find out the potential molecules against the MPXV-CCP. The top five hits were selected after screening and processed for exhaustive docking based on the docked score of ≤ -9.5 kcal/mol. Later, the top three hits based on the exhaustive-docking score and interaction profile were selected to perform MD simulations. The overall RMSD suggested that two compounds, SC75741 and ammonium glycyrrhizinate, showed a highly stable complex with a standard deviation of 0.18 and 0.23 nm, respectively. Later, the MM/GBSA binding free energies of complexes showed significant binding strength with ΔGTOTAL from -21.59 to -15 kcal/mol. This report reported the potential inhibitory activity of SC75741 and ammonium glycyrrhizinate against MPXV-CCP by competitively inhibiting the binding of the native substrate.

Antimycobacterial Activity of Solid Lipid Microparticles Loaded with Ursolic Acid and Oleanolic Acid: In Vitro, In Vivo, and Toxicity Assessments

Ursolic acid (UA) and oleanolic acid (OA) are hydrophobic triterpenoid isomers with demonstrated anti-mycobacterial (Mtb) and immune-regulatory properties, although their poor solubility limits clinical use. We report the development of solid lipid microparticles (SLMs) as delivery vehicles for UA and OA and evaluate their anti-Mtb efficacy in vitro and in vivo, as well as their acute toxicity. SLMs measured 0.7-0.89 µM in size, with complete in vitro release of OA and UA at 40 and 32 h, respectively. The minimum inhibitory concentration (MIC) of SLMs loaded with OA and UA was 40 µg/mL SLMs + 20 µg/mL OA + 20 µg/mL UA for drug-sensitive Mtb and 80 µg/mL SLMs + 40 µg/mL OA + 40 µg/mL UA for multidrug-resistant (MDR) Mtb. These SLMs showed an efficient reduction in Mtb burden in infected alveolar macrophages. In a murine model of late-stage progressive MDR-TB, aerosolized delivery of SLMs containing OA and UA via a metered-dose inhaler significantly reduced pulmonary bacterial loads and extended survival. In vivo, acute toxicity studies revealed no mortality or signs of toxicity. These findings demonstrate that SLMs are an optimal delivery system for terpenoids, providing potent in vitro and in vivo anti-TB activity with an excellent safety profile.

Cytotoxic Autophagy: A Novel Treatment Paradigm against Breast Cancer Using Oleanolic Acid and Ursolic Acid

BACKGROUND

Oleanolic acid (OA) and Ursolic acid (UA) are bioactive triterpenoids. Reported activities vary with the dose used for testing their activities in vitro. Studies using doses of ≥20 µM showed apoptosis activities in cancer cells. However, reported drug levels in circulation achieved by oral administration of UA and OA are ≤2 µM, thus limiting their use for treatment or delivering a combination treatment.

MATERIALS AND METHODS

The present report demonstrates the efficacy of OA, UA, and OA + UA on tumor cell-specific cytotoxicity at low doses (5 µM to 10 µM) in breast cancer (BrCa) cell lines MCF7 and MDA-MB231.

RESULTS

The data show that both OA and UA killed BrCa cells at low doses, but were significantly less toxic to MCF-12A, a non-tumorigenic cell line. Moreover, OA + UA at ≤10 µM was lethal to BrCa cells. Mechanistic studies unraveled the significant absence of apoptosis, but their cytotoxicity was due to the induction of excessive autophagy at a OA + UA dose of 5 µM each. A link to drug-induced cytotoxic autophagy was established by demonstrating a lack of their cytotoxicity by silencing the autophagy-targeting genes (ATGs), which prevented OA-, UA-, or OA + UA-induced cell death. Further, UA or OA + UA treatment of BrCa cells caused an inhibition of PI3 kinase-mediated phosphorylation of Akt/mTOR, the key pathways that regulate cancer cell survival, metabolism, and proliferation.

DISCUSSION

Combinations of a PI3K inhibitor (LY294002) with OA, UA, or OA + UA synergistically inhibited BrCa cell survival. Therefore, the dominance of cytotoxic autophagy by inhibiting PI3K-mediated autophagy may be the primary mechanism of PTT-induced anticancer activity in BrCa cells.

CONCLUSION

These results suggest it would be worthwhile testing combined OA and UA in clinical settings.

Multimodal modulation of hepatic ischemia/reperfusion-induced injury by phytochemical agents: A mechanistic evaluation of hepatoprotective potential and safety profiles

BACKGROUND

Hepatic ischemia-reperfusion (I/R) injury is a clinically fundamental phenomenon that occurs through liver resection surgery, trauma, shock, and transplantation.

AIMS OF THE REVIEW

This review article affords an expanded and comprehensive overview of various natural herbal ingredients that have demonstrated hepatoprotective effects against I/R injury through preclinical studies in animal models.

MATERIALS AND METHODS

For the objective of this investigation, an extensive examination was carried out utilizing diverse scientific databases involving PubMed, Google Scholar, Science Direct, Egyptian Knowledge Bank (EKB), and Research Gate. The investigation was conducted based on specific identifiable terms, such as hepatic ischemia/reperfusion injury, liver resection and transplantation, cytokines, inflammation, NF-kB, interleukins, herbs, plants, natural ingredients, phenolic extract, and aqueous extract.

RESULTS

Bioactive ingredients derived from ginseng, curcumin, resveratrol, epigallocatechin gallate, quercetin, lycopene, punicalagin, crocin, celastrol, andrographolide, silymarin, and others and their effects on hepatic IRI were discussed. The specific mechanisms of action, signaling pathways, and clinical relevance for attenuation of liver enzymes, cytokine production, immune cell infiltration, oxidative damage, and cell death signaling in rodent studies are analyzed in depth. Their complex molecular actions involve modulation of pathways like TLR4, NF-κB, Nrf2, Bcl-2 family proteins, and others.

CONCLUSION

The natural ingredients have promising values in the protection and treatment of various chronic aggressive clinical conditions, and that need to be evaluated on humans by clinical studies.

Chemical components with biological activities in the roots of Ilex pubescens

Two new triterpenoids, ilexsaponin U (1) and ilexsaponin V (2), and three new phenylpropanoids, pubescenoside S (3), pubescenoside T (38), and pubescenoside U (39), along with thirty-four existing compounds were isolated from the roots of Ilex pubescens. The elucidation of their structures involved comprehensive spectroscopic techniques, including IR, UV, HR-ESI-MS, and NMR experiments. The anti-inflammatory effects of almost all the compounds were evaluated in LPS-induced RAW264.7 cells. Among these, compounds 1, 4, 8, 11, 12, 26, 27, 29 and 33 exhibited varying degrees of inhibition of inflammatory factors. Notably, compounds 1, 4 and 8 significantly inhibited the mRNA levels of iNOS, IL-6, IL-1β and TNFα, comparable to or exceeding the effect of the positive control (dexamethasone, DEX). We also evaluated the cardioprotective effects of these compounds in OGD/R-induced H9c2 cells. The results revealed that compounds 2, 3, 7, 8, 26, 35, 36 and 37 at 20 μM significantly increased cell viability by 24.9 ± 3.4%, 28.0 ± 0.3%, 37.6 ± 0.2%, 44.86 ± 0.5%, 9.47 ± 2.1%, 23.9 ± 0.4%, 39.5 ± 3.1% and 28.2 ± 0.1%, respectively. Some of them exhibited effects equal to or greater than that of the positive control (diazoxide, DZ) at 100 μM, showing a 21.9 ± 3.0% increase.

Roles of natural products on myokine expression and secretion in skeletal muscle atrophy

Skeletal muscles serve both in movement and as endocrine organs. Myokines secreted by skeletal muscles activate biological functions within muscles and throughout the body via autocrine, paracrine, and/or endocrine pathways. Skeletal muscle atrophy can influence myokine expression and secretion, while myokines can impact the structure and function of skeletal muscles. Regulating the expression and secretion of myokines through the pharmacological approach is a strategy for alleviating skeletal muscle atrophy. Natural products possess complex structures and chemical properties. Previous studies have demonstrated that various natural products exert beneficial effects on skeletal muscle atrophy. This article reviewed the regulatory effects of natural products on myokines and summarized the research progress on skeletal muscle atrophy associated with myokine regulation. The focus is on how small-molecule natural products affect the regulation of interleukin 6 (IL-6), irisin, myostatin, IGF-1, and FGF-21 expression. We contend that the development of small-molecule natural products targeting the regulation of myokines holds promise in combating skeletal muscle atrophy.

Therapeutic Potential of Terpenoids in Cancer Treatment: Targeting Mitochondrial Pathways

BACKGROUND

In recent decades, natural compounds have been considered a significant source of new antitumor medicines due to their unique advantages. Several in vitro and in vivo studies have focused on the effect of terpenoids on apoptosis mediated by mitochondria in malignant cells.

RECENT FINDINGS

In this review article, we focused on six extensively studied terpenoids, including sesquiterpenes (dihydroartemisinin and parthenolide), diterpenes (oridonin and triptolide), and triterpenes (betulinic acid and oleanolic acid), and their efficacy in targeting mitochondria to induce cell death. Terpenoid-induced mitochondria-related cell death includes apoptosis, pyroptosis, necroptosis, ferroptosis, autophagy, and necrosis caused by mitochondrial permeability transition. Apoptosis and autophagy interact in meaningful ways. In addition, in view of several disadvantages of terpenoids, such as low stability and bioavailability, advances in research on combination chemotherapy and chemical modification were surveyed.

CONCLUSION

This article deepens our understanding of the association between terpenoids and mitochondrial cell death, presenting a hypothetical basis for the use of terpenoids in anticancer management.

The effects of pomegranate (Punica granatum) on nonalcoholic fatty liver disease: A systematic review of in vivo interventional studies

Nonalcoholic fatty liver disease (NAFLD) is a disorder in which excess fat accumulates in hepatocytes and can lead to serious complications. Oxidative stress is one of the leading causes of NAFLD. Pomegranates are considered antioxidant-rich fruit. This systematic review study was aimed to investigate the impact of pomegranate on NAFLD. PubMed, Scopus, and Google Scholar databases/search engines (from inception up to July 2023) were searched for interventional studies (human and animal) that examined the effects of supplementation with different parts of pomegranate including fruits, peels, seeds, or flower on NAFLD outcomes. A total of 222 articles were retrieved following the initial search. After excluding duplicates, the title and abstract of 114 articles were screened. Afterward, irrelevant articles were removed and the full texts of the remaining 27 articles were reviewed. Eventually, 19 articles (16 animal and three human interventional studies) that met the inclusion criteria, published between 2009 and 2023, were included in this systematic review. Our study indicates the potential beneficial effects of different parts of pomegranate on the improvement of NAFLD. However, given that the majority of the included articles were animal studies, further investigations in the form of human clinical trials are warranted to suggest a clinical indication of such interventions.

Therapeutic potential of oleanolic acid in liver diseases

Liver-associated diseases affect millions of individuals worldwide. In developed countries, the incidence of viral hepatitis is reducing due to advancements in disease prevention, diagnosis, and treatment. However, with improvements in living standards, the prevalence of metabolic liver diseases, such as non-alcoholic fatty liver disease and alcohol-related liver disease, is expected to increase; notably, this rise in the prevalence of metabolic liver disease can lead to the development of more severe liver diseases, including liver failure, cirrhosis, and liver cancer. The growing demand for natural alternative therapies for chronic diseases has highlighted the importance of studying the pharmacology of bioactive compounds in plants. One such compound is oleanolic acid (OA), a pentacyclic triterpenoid known for its antioxidant, anti-inflammatory, anti-ulcer, antibacterial, antiviral, antihypertensive, anti-obesity, anticancer, anti-diabetic, cardioprotective, hepatoprotective, and anti-neurodegenerative properties. Recent studies have demonstrated that OA treatment can reduce the risk of pathological liver damage, ultimately alleviating liver dysregulation and restoring overall liver function. This review aims to explore the latest research on the biological effects of OA and its derivatives. Notably, it explores the mechanisms of action of these compounds in both in vitro and in vivo research models and, ultimately, highlights OA as a promising candidate for alternative therapies in the treatment and management of chronic liver disease.

Exploring the Potential Use of Natural Products Together with Alkalization in Cancer Therapy

Cancer treatment is a significant focus in medicine, owing to the increasing global incidence of cancers. Patients with advanced cancers that do not respond to conventional therapies have limited options and an unfavorable prognosis. Consequently, researchers are investigating complementary approaches to conventional treatments. One such approach is alkalization therapy, which aims to neutralize the acidic tumor microenvironment (TME) by increasing its pH level. The acidic TME promotes inflammation, tumor progression, and drug resistance. Alkalization therapy has been demonstrated to be effective for various cancers. In addition, natural products, such as triterpenoids, parthenolides, fulvic acid, Taxus yunnanensis, and apple pectin have the potential to alleviate symptoms, maintain physical fitness, and improve treatment outcomes of cancer patients through their anti-inflammatory, antioxidant, and anticancer properties. In this review, we focus on the effects of alkalization therapy and natural products on cancer. Furthermore, we present a case series of advanced cancer patients who received alkalization therapy and natural products alongside standard treatments, resulting in long-term survival. We posit that alkalization therapy together with supplementation with natural products may confer benefits to cancer patients, by mitigating the side effects of chemotherapy and complementing standard treatments. However, further research is warranted to validate these clinical findings.

Oleanolic acid and its analogues: promising therapeutics for kidney disease

Kidney diseases pose a significant threat to human health due to their high prevalence and mortality rates. Worryingly, the clinical use of drugs for kidney diseases is associated with more side effects, so more effective and safer treatments are urgently needed. Oleanolic acid (OA) is a common pentacyclic triterpenoid that is widely available in nature and has been shown to have protective effects in kidney disease. However, comprehensive studies on its role in kidney diseases are still lacking. Therefore, this article first explores the botanical sources, pharmacokinetics, derivatives, and safety of OA, followed by a summary of the anti-inflammatory, immunomodulatory, anti-oxidative stress, autophagy-enhancing, and antifibrotic effects of OA and its analogues in renal diseases, and an analysis of the molecular mechanisms, aiming to provide further insights for the development of novel drugs for the treatment of kidney diseases.

Self-controlled in silico gene knockdown strategies to enhance the sustainable production of heterologous terpenoid by Saccharomyces cerevisiae

Microbial bioengineering is a growing field for producing plant natural products (PNPs) in recent decades, using heterologous metabolic pathways in host cells. Once heterologous metabolic pathways have been introduced into host cells, traditional metabolic engineering techniques are employed to enhance the productivity and yield of PNP biosynthetic routes, as well as to manage competing pathways. The advent of computational biology has marked the beginning of a novel epoch in strain design through in silico methods. These methods utilize genome-scale metabolic models (GEMs) and flux optimization algorithms to facilitate rational design across the entire cellular metabolic network. However, the implementation of in silico strategies can often result in an uneven distribution of metabolic fluxes due to the rigid knocking out of endogenous genes, which can impede cell growth and ultimately impact the accumulation of target products. In this study, we creatively utilized synthetic biology to refine in silico strain design for efficient PNPs production. OptKnock simulation was performed on the GEM of Saccharomyces cerevisiae OA07, an engineered strain for oleanolic acid (OA) bioproduction that has been reported previously. The simulation predicted that the single deletion of fol1, fol2, fol3, abz1, and abz2, or a combined knockout of hfd1, ald2 and ald3 could improve its OA production. Consequently, strains EK1∼EK7 were constructed and cultivated. EK3 (OA07△fol3), EK5 (OA07△abz1), and EK6 (OA07△abz2) had significantly higher OA titers in a batch cultivation compared to the original strain OA07. However, these increases were less pronounced in the fed-batch mode, indicating that gene deletion did not support sustainable OA production. To address this, we designed a negative feedback circuit regulated by malonyl-CoA, a growth-associated intermediate whose synthesis served as a bypass to OA synthesis, at fol3, abz1, abz2, and at acetyl-CoA carboxylase-encoding gene acc1, to dynamically and autonomously regulate the expression of these genes in OA07. The constructed strains R_3A, R_5A and R_6A had significantly higher OA titers than the initial strain and the responding gene-knockout mutants in either batch or fed-batch culture modes. Among them, strain R_3A stand out with the highest OA titer reported to date. Its OA titer doubled that of the initial strain in the flask-level fed-batch cultivation, and achieved at 1.23 ± 0.04 g L-1 in 96 h in the fermenter-level fed-batch mode. This indicated that the integration of optimization algorithm and synthetic biology approaches was efficiently rational for PNP-producing strain design.

The Effect and Mechanism of Oleanolic Acid in the Treatment of Metabolic Syndrome and Related Cardiovascular Diseases

Metabolic syndromes (MetS) and related cardiovascular diseases (CVDs) pose a serious threat to human health. MetS are metabolic disorders characterized by obesity, dyslipidemia, and hypertension, which increase the risk of CVDs' initiation and development. Although there are many availabile drugs for treating MetS and related CVDs, some side effects also occur. Considering the low-level side effects, many natural products have been tried to treat MetS and CVDs. A five-cyclic triterpenoid natural product, oleanolic acid (OA), has been reported to have many pharmacologic actions such as anti-hypertension, anti-hyperlipidemia, and liver protection. OA has specific advantages in the treatment of MetS and CVDs. OA achieves therapeutic effects through a variety of pathways, attracting great interest and playing a vital role in the treatment of MetS and CVDs. Consequently, in this article, we aim to review the pharmacological actions and potential mechanisms of OA in treating MetS and related CVDs.

Natural products in anti-tuberculosis host-directed therapy

Given that the disease progression of tuberculosis (TB) is primarily related to the host's immune status, it has been gradually realized that chemotherapy that targets the bacteria may never, on its own, wholly eradicate Mycobacterium tuberculosis, the causative agent of TB. The concept of host-directed therapy (HDT) with immune adjuvants has emerged. HDT could potentially interfere with infection and colonization by the pathogens, enhance the protective immune responses of hosts, suppress the overwhelming inflammatory responses, and help to attain a state of homeostasis that favors treatment efficacy. However, the HDT drugs currently being assessed in combination with anti-TB chemotherapy still face the dilemmas arising from side effects and high costs. Natural products are well suited to compensate for these shortcomings by having gentle modulatory effects on the host immune responses with less immunopathological damage at a lower cost. In this review, we first summarize the profiles of anti-TB immunology and the characteristics of HDT. Then, we focus on the rationale and challenges of developing and implementing natural products-based HDT. A succinct report of the medications currently being evaluated in clinical trials and preclinical studies is provided. This review aims to promote target-based screening and accelerate novel TB drug discovery.

Integrating network pharmacology and animal experimental validation to investigate the action mechanism of oleanolic acid in obesity

BACKGROUND

Obesity, a condition associated with the development of widespread cardiovascular disease, metabolic disorders, and other health complications, has emerged as a significant global health issue. Oleanolic acid (OA), a pentacyclic triterpenoid compound that is widely distributed in various natural plants, has demonstrated potential anti-inflammatory and anti-atherosclerotic properties. However, the mechanism by which OA fights obesity has not been well studied.

METHOD

Network pharmacology was utilized to search for potential targets and pathways of OA against obesity. Molecular docking and molecular dynamics simulations were utilized to validate the interaction of OA with core targets, and an animal model of obesity induced by high-fat eating was then employed to confirm the most central of these targets.

RESULTS

The network pharmacology study thoroughly examined 42 important OA targets for the treatment of obesity. The key biological processes (BP), cellular components (CC), and molecular functions (MF) of OA for anti-obesity were identified using GO enrichment analysis, including intracellular receptor signaling, intracellular steroid hormone receptor signaling, chromatin, nucleoplasm, receptor complex, endoplasmic reticulum membrane, and RNA polymerase II transcription Factor Activity. The KEGG/DAVID database enrichment study found that metabolic pathways, PPAR signaling pathways, cancer pathways/PPAR signaling pathways, insulin resistance, and ovarian steroidogenesis all play essential roles in the treatment of obesity and OA. The protein-protein interaction (PPI) network was used to screen nine main targets: PPARG, PPARA, MAPK3, NR3C1, PTGS2, CYP19A1, CNR1, HSD11B1, and AGTR1. Using molecular docking technology, the possible binding mechanism and degree of binding between OA and each important target were validated, demonstrating that OA has a good binding potential with each target. The molecular dynamics simulation's Root Mean Square Deviation (RMSD), and Radius of Gyration (Rg) further demonstrated that OA has strong binding stability with each target. Additional animal studies confirmed the significance of the core target PPARG and the core pathway PPAR signaling pathway in OA anti-obesity.

CONCLUSION

Overall, our study utilized a multifaceted approach to investigate the value and mechanisms of OA in treating obesity, thereby providing a novel foundation for the identification and development of natural drug treatments.

Phytoimmunomodulators: A review of natural modulators for complex immune system

In the past few decades, the medicinal properties of plants and their effects on the human immune system are being studied extensively. Plants are an incredible source of traditional medicines that help cure various diseases, including altered immune mechanisms and are economical and benign compared to allopathic medicines. Reported data in written documents such as Traditional Chinese medicine, Indian Ayurvedic medicine support the supplementation of botanicals for immune defense reactions in the body and can lead to safe and effective immunity responses. Additionally, some botanicals are well-identified as magical herbal remedies because they act upon the pathogen directly and help boost the immunity of the host. Chemical compounds, also known as phytochemicals, obtained from these botanicals looked promising due to their effects on the human immune system by modulating the lymphocytes which subsequently reduce the chances of getting infected. This paper summarises most documented phytochemicals and how they act on the immune system, their properties and possible mechanisms, screening conventions, formulation guidelines, comparison with synthetic immunity-enhancers, marketed immunity-boosting products, and immune-booster role in the ongoing ghastly corona virus wave. However, it focuses mainly on plant metabolites as immunomodulators. In addition, it also sheds light on the current advancements and future possibilities in this field. From this thorough study, it can be stated that the plant-based secondary metabolites contribute significantly to immunity building and could prove to be valuable medicaments for the design and development of novel immunomodulators even for a pandemic like COVID-19.

Plants with potential anti-ulcerogenic activity and possible mechanism of actions based on their phyto-constitutional profile

Gastric ulcer, the most common disorder of the digestive tract is formed due to an imbalance between acid and mucus content of the stomach. However, the currently used western therapeutic regimens have many drawbacks like adverse effects, recurrence of gastric ulcers, are expensive, and also, may have interactions with other drugs. Hence, there is a need for effective alternative therapy. Medicinal herbs have been used since ancient times to treat several diseases and are also evidenced to be effective against gastric ulcers. It is also evident that medicinal herbs have been proved to be equally effective or superior as compared to the existing synthetic medicines. In this review, five herbs have been taken into consideration and assumed to be effective against gastric ulcers. Abrus mollis, Korean Thistle (Cirsium japonicum var. maackii), Astralagus complanatus Bunge, Bauhinia monandra, and Embelia ribes Burm f. are the herbs whose data is been collected and reviewed for their potential gastro-protective action. Although, their side effects and toxicity profile need to be further evaluated. Hence, the purpose of this review is to gather evidence of these five medicinal herbs and their probable mechanism of action against gastric ulcers based on their phyto-constitutional profile.

Pentacyclic triterpene-amino acid derivatives induced apoptosis and autophagy in tumor cells, affected the JNK and PI3K/AKT/mTOR pathway

A series of pentacyclic triterpene-amino acid derivatives were synthesized and tested for anti-proliferative activity. The results showed that most of the target compounds had good anti-proliferative activity. 2c did not contain protecting groups and hydrochloride, had excellent cytotoxicity, so it had been selected for further study in the mechanism of action in T24 cells. The data from transcriptome sequencing indicated that 2c was found to be closely related to apoptosis and autophagy. Observation of fluorescence staining and analysis from flow cytometry demonstrated that 2c induced apoptosis and cause cell cycle arrest in S/G2 phase in T24 cells. Molecular mechanism studies exhibited that 2c induced apoptosis in the intrinsic and extrinsic pathways. 2c also induced cellular autophagy in T24 cells. Results from Western Blotting showed that 2c could activate JNK pathway and inhibit PI3K/AKT/mTOR pathway. In conclusion, 2c was deserved further investigation in the field of anti-tumor.

Natural compounds as lactate dehydrogenase inhibitors: potential therapeutics for lactate dehydrogenase inhibitors-related diseases

Lactate dehydrogenase (LDH) is a crucial enzyme involved in energy metabolism and present in various cells throughout the body. Its diverse physiological functions encompass glycolysis, and its abnormal activity is associated with numerous diseases. Targeting LDH has emerged as a vital approach in drug discovery, leading to the identification of LDH inhibitors among natural compounds, such as polyphenols, alkaloids, and terpenoids. These compounds demonstrate therapeutic potential against LDH-related diseases, including anti-cancer effects. However, challenges concerning limited bioavailability, poor solubility, and potential toxicity must be addressed. Combining natural compounds with LDH inhibitors has led to promising outcomes in preclinical studies. This review highlights the promise of natural compounds as LDH inhibitors for treating cancer, cardiovascular, and neurodegenerative diseases.

Synthesis of β,γ-Unsaturated Aliphatic Acids via Ligand-Enabled Dehydrogenation

α,β-Dehydrogenation of aliphatic acids has been realized through both enolate and β-C-H metalation pathways. However, the synthesis of isolated β,γ-unsaturated aliphatic acids via dehydrogenation has not been achieved to date. Herein, we report the ligand-enabled β,γ-dehydrogenation of abundant and inexpensive free aliphatic acids, which provides a new synthetic disconnection as well as a versatile platform for the downstream functionalization of complex molecules at remote γ-sites. A variety of free aliphatic acids, including acyclic and cyclic systems with ring sizes from five-membered to macrocyclic, undergo efficient dehydrogenation. Notably, this protocol features good chemoselectivity in the presence of more accessible α-C-H bonds and excellent regioselectivity in fused bicyclic scaffolds. The utility of this protocol has been demonstrated by the late-stage functionalization of a series of bioactive terpene natural products at the γ-sites. Further functionalization of the β,γ-double bond allows for the installation of covalent warheads, including epoxides, aziridines, and β-lactones, into complex natural product scaffolds, which are valuable for targeted covalent drug discovery.

Ocimum sanctum Alters the Lipid Landscape of the Brain Cortex and Plasma to Ameliorate the Effect of Photothrombotic Stroke in a Mouse Model

Stroke-like injuries in the brain result in not only cell death at the site of the injury but also other detrimental structural and molecular changes in regions around the stroke. A stroke-induced alteration in the lipid profile interferes with neuronal functions such as neurotransmission. Preventing these unfavorable changes is important for recovery. Ocimum sanctum (Tulsi extract) is known to have anti-inflammatory and neuroprotective properties. It is possible that Tulsi imparts a neuroprotective effect through the lipophilic transfer of active ingredients into the brain. Hence, we examined alterations in the lipid profile in the cerebral cortex as well as the plasma of mice with a photothrombotic-ischemic-stroke-like injury following the administration of a Tulsi extract. It is also possible that the lipids present in the Tulsi extract could contribute to the lipophilic transfer of active ingredients into the brain. Therefore, to identify the major lipid species in the Tulsi extract, we performed metabolomic and untargeted lipidomic analyses on the Tulsi extract. The presence of 39 molecular lipid species was detected in the Tulsi extract. We then examined the effect of a treatment using the Tulsi extract on the untargeted lipidomic profile of the brain and plasma following photothrombotic ischemic stroke in a mouse model. Mice of the C57Bl/6j strain, aged 2-3 months, were randomly divided into four groups: (i) Sham, (ii) Lesion, (iii) Lesion plus Tulsi, and (iv) Lesion plus Ibuprofen. The cerebral cortex of the lesioned hemisphere of the brain and plasma samples were collected for untargeted lipidomic profiling using a Q-Exactive Mass Spectrometer. Our results documented significant alterations in major lipid groups, including PE, PC, neutral glycerolipids, PS, and P-glycerol, in the brain and plasma samples from the photothrombotic stroke mice following their treatment with Tulsi. Upon further comparison between the different study groups of mice, levels of MGDG (36:4), which may assist in recovery, were found to be increased in the brain cortexes of the mice treated with Tulsi when compared to the other groups (p < 0.05). Lipid species such as PS, PE, LPG, and PI were commonly altered in the Sham and Lesion plus Tulsi groups. The brain samples from the Sham group were specifically enriched in many species of glycerol lipids and had reduced PE species, while their plasma samples showed altered PE and PS species when compared to the Lesion group. LPC (16:1) was found in the Tulsi extract and was significantly increased in the brains of the PTL-plus-Tulsi-treated group. Our results suggest that the neuroprotective effect of Tulsi on cerebral ischemia may be partially associated with its ability to regulate brain and plasma lipids, and these results may help provide critical insights into therapeutic options for cerebral ischemia or brain lesions.

Engineering natural molecule-triggered genetic control systems for tunable gene- and cell-based therapies

The ability to precisely control activities of engineered designer cells provides a novel strategy for modern precision medicine. Dynamically adjustable gene- and cell-based precision therapies are recognized as next generation medicines. However, the translation of these controllable therapeutics into clinical practice is severely hampered by the lack of safe and highly specific genetic switches controlled by triggers that are nontoxic and side-effect free. Recently, natural products derived from plants have been extensively explored as trigger molecules to control genetic switches and synthetic gene networks for multiple applications. These controlled genetic switches could be further introduced into mammalian cells to obtain synthetic designer cells for adjustable and fine tunable cell-based precision therapy. In this review, we introduce various available natural molecules that were engineered to control genetic switches for controllable transgene expression, complex logic computation, and therapeutic drug delivery to achieve precision therapy. We also discuss current challenges and prospects in translating these natural molecule-controlled genetic switches developed for biomedical applications from the laboratory to the clinic.

Phytocompounds and their molecular targets in immunomodulation: a review

Immune cells are important for the healthy function of every organ. The homeostasis of the immune system is selfregulated by T-cells, B-cells, and natural killer cells. The immunomodulation process of immune cells is part of the immunotherapy. According to therapeutic methods of immune responses are categorized as inducing (immunostimulant), amplification (immune booster), attenuation (immunomodulation), and prevention (immunosuppressive) actions. The prevalence of chronic immunological diseases like viral infections, allergies, and cancer is mainly due to the over-activation of the immune system. Further, immunomodulators are reported to manage the severity of chronic immunological disorders. Moreover, these immunomodulator-acting proteins are identified as potential molecular targets for the regulation of the immune system. Moreover, natural compound like phytocompounds are known to bind these targets and modulates the immune system. The specialized phytocompounds like curcumin, quercetin, stilbenes, flavonoids, and lignans are shown the immunomodulatory actions and ameliorate the immunological disorders. The present scenario of a COVID-19 pandemic situation has taught us the need to focus on strengthening the immune system and the development of the most promising immunotherapeutics. This review is focused on an overview of various phytocompounds and their molecular targets for the management of immunological disorders via immunosuppressants and immunostimulants actions.

Variation in Terpenoid and Flavonoid Content in Different Samples of Salvia semiatrata Collected from Oaxaca, Mexico, and Its Effects on Antinociceptive Activity

Salvia semiatrata Zucc. (Lamiaceae) is endemic to Oaxaca, Mexico, and is known for its analgesic properties. Terpenoids and phenolic compounds with antinociceptive potential have been characterised from this species. The aim of this research was to determine the variation in terpenoids and flavonoids in ethyl acetate extracts of S. semiatrata collected from ten different localities, as well as to evaluate the antinociceptive effect between plants with higher and lower contents of these secondary metabolites. Quantification of S. semiatrata compounds was performed via HPLC-DAD, whereas in vivo evaluation of the antinociceptive effect was performed via formalin test. The results showed that the most abundant groups of metabolites are oleanolic acid (89.60-59.20 µg/mg), quercetin (34.81-16.28 µg/mg), catechin (11.30-9.30 µg/mg), and 7-keto-neoclerodan-3,13-dien-18,19:15,16-diolide (7-keto) (8.01-4.76 µg/mg). Principal component and canonical correspondence analysis showed that the most contrasting localities in terms of compound content and climatic variables are Miahuatlán and Santiago Huauclilla. The differences in metabolite content between the two locations did not affect the antinociceptive effects evaluated at a dose of 300 mg/kg, p.o. In conclusion, the results indicate that S. semiatrata is effective in relieving pain, regardless of the site of collection, reinforcing its traditional use as analgesic.

Genus Equisetum L: Taxonomy, toxicology, phytochemistry and pharmacology

INTRODUCTION

The genus Equisetum (Equisetaceae) is cosmopolitan in distribution, with 41 recognized species. Several species of Equisetum are widely used in treating genitourinary and related diseases, inflammatory and rheumatic problems, hypertension, and wound healing in traditional medicine practices worldwide. This review intends to present information on the traditional uses, phytochemical components, pharmacological activities, and toxicity of Equisetum spp. and to analyze the new insights for further study.

METHODS

Relevant literature has been scanned and collected via various electronic repositories, including PubMed, Science Direct, Google Scholar, Springer Connect, and Science Online, from 1960 to 2022.

RESULTS

Sixteen Equisetum spp. were documented as widely used in traditional medicine practices by different ethnic groups throughout the world. A total of 229 chemical compounds were identified from Equisetum spp. with the major group of constituents being flavonol glycosides and flavonoids. The crude extracts and phytochemicals of Equisetum spp. exhibited significant antioxidant, antimicrobial, anti-inflammatory, antiulcerogenic, antidiabetic, hepatoprotective, and diuretic properties. A wide range of studies have also demonstrated the safety of Equisetum spp.

CONCLUSION

The reported pharmacological properties of Equisetum spp. support its use in traditional medicine, though there are gaps in understanding the traditional usage of these plants for clinical experiments. The documented information revealed that the genus is not only a great herbal remedy but also has several bioactives with the potential to be discovered as novel drugs. Detailed scientific investigation is still needed to fully understand the efficacy of this genus; hence, very few Equisetum spp. were studied in detail for phytochemical and pharmacological investigation. Moreover, its bioactives, structure-activity connection, in vivo activity, and associated mechanism of action ought to be explored further.

Metabolic changes in kidney stone disease

Kidney stone disease (KSD) is one of the earliest medical diseases known, but the mechanism of its formation and metabolic changes remain unclear. The formation of kidney stones is a extensive and complicated process, which is regulated by metabolic changes in various substances. In this manuscript, we summarized the progress of research on metabolic changes in kidney stone disease and discuss the valuable role of some new potential targets. We reviewed the influence of metabolism of some common substances on stone formation, such as the regulation of oxalate, the release of reactive oxygen species (ROS), macrophage polarization, the levels of hormones, and the alternation of other substances. New insights into changes in substance metabolism changes in kidney stone disease, as well as emerging research techniques, will provide new directions in the treatment of stones. Reviewing the great progress that has been made in this field will help to improve the understanding by urologists, nephrologists, and health care providers of the metabolic changes in kidney stone disease, and contribute to explore new metabolic targets for clinical therapy.

Mesoporous Silica Nanoparticles as a Gene Delivery Platform for Cancer Therapy

Cancer remains a major global health challenge. Traditional chemotherapy often results in side effects and drug resistance, necessitating the development of alternative treatment strategies such as gene therapy. Mesoporous silica nanoparticles (MSNs) offer many advantages as a gene delivery carrier, including high loading capacity, controlled drug release, and easy surface functionalization. MSNs are biodegradable and biocompatible, making them promising candidates for drug delivery applications. Recent studies demonstrating the use of MSNs for the delivery of therapeutic nucleic acids to cancer cells have been reviewed, along with their potential as a tool for cancer therapy. The major challenges and future interventions of MSNs as gene delivery carriers for cancer therapy are discussed.

Bioefficacy of ursolic acid and its derivatives isolated from Catharanthus roseus (L) G. Don leaf against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi larvae

The aim of the present study was to identify the active principle from Catharanthus roseus leaf using larvicidal bioassay against three mosquito species viz. Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi. Preliminary studies of the three successive extracts such as hexane, chloroform, and methanol against Ae. aegypti larvae showed that the chloroform extract was more active with LC₅₀ and LC₉₀ values of 40.09 ppm and 189.15 ppm respectively. Bioassay guided fractionation of the active chloroform extract resulted in the isolation of a triterpenoid (ursolic acid) as the active constituent. Three derivatives acetate, formate, and benzoate were prepared using this, and they were tested for their larvicidal activity against three mosquito species. The acetyl derivative was highly active against all the three species compared to the parent compound ursolic acid; the activities of benzoate and formate were higher than ursolic acid when tested against Cx. quinquefasciatus. This is the first report related to ursolic acid from C. roseus with mosquito larvicidal activity. The pure compound could be considered for medicinal and other pharmacological applications in future.

Targeting DNA polymerase β elicits synthetic lethality with mismatch repair deficiency in acute lymphoblastic leukemia

Mismatch repair (MMR) deficiency has been linked to thiopurine resistance and hypermutation in relapsed acute lymphoblastic leukemia (ALL). However, the repair mechanism of thiopurine-induced DNA damage in the absence of MMR remains unclear. Here, we provide evidence that DNA polymerase β (POLB) of base excision repair (BER) pathway plays a critical role in the survival and thiopurine resistance of MMR-deficient ALL cells. In these aggressive resistant ALL cells, POLB depletion and its inhibitor oleanolic acid (OA) treatment result in synthetic lethality with MMR deficiency through increased cellular apurinic/apyrimidinic (AP) sites, DNA strand breaks and apoptosis. POLB depletion increases thiopurine sensitivities of resistant cells, and OA synergizes with thiopurine to kill these cells in ALL cell lines, patient-derived xenograft (PDX) cells and xenograft mouse models. Our findings suggest BER and POLB's roles in the process of repairing thiopurine-induced DNA damage in MMR-deficient ALL cells, and implicate their potentials as therapeutic targets against aggressive ALL progression.

Ursolic acid nanoparticles for glioblastoma therapy

BACKGROUND

Glioblastoma multiforme (GBM) is the most common and fatal primary tumor in the central nervous system (CNS). The effect of chemotherapy of GBM is limited due to the existence of blood-brain barrier (BBB). The aim of this study is to develop self-assembled nanoparticles (NPs) of ursolic acid (UA) for GBM treatment.

METHODS

UA NPs were synthesized by solvent volatilization method. Western blot analysis fluorescent staining and flow cytometry were launched to explore the anti-glioblastoma mechanism of UA NPs. The antitumor effects of UA NPs were further confirmed in vivo using intracranial xenograft models.

RESULTS

UA were successfully prepared. In vitro, UA NPs could significantly increase the protein levels of cleaved-caspase 3 and LC3-II to strongly eliminate glioblastoma cells through autophagy and apoptosis. In the intracranial xenograft models, UA NPs could further effectively enter the BBB, and greatly improve the survival time of the mice.

CONCLUSIONS

We successfully synthesized UA NPs which could effectively enter the BBB and show strong anti-tumor effect which may have great potential in the treatment of human glioblastoma.

Recent advances in natural small molecules as drug delivery systems

Drug delivery systems (DDSs) are a multidisciplinary approach toward the effective delivery of drugs to their target sites. Natural small molecule (NSM) compounds with anticancer activity, self-assembly and co-assembly functions show great potential for application as novel DDSs in the biomedical field. NSMs are widely sourced, have many modification sites, and readily form hydrogen bonds, π-π interactions, van der Waals interactions, and other non-covalent bonds in solvents, resulting in ordered structures. Moreover, their good biocompatibility and bioactivity allow compositions based on these compounds to be used in life science applications such as tissue engineering, drug delivery and cell imaging, showing the potential medical value of NSMs as DDSs. In this review, we summarise the role, assembly principles and applications of natural products such as triterpenoids, diterpenoids, sterols, alkaloids and polysaccharides in the construction of small molecule systems, which are expected to provide an important reference for the development of more active natural nanomaterials and the study of single or multi-component interactions.

Suppression of SIRT1/FXR signaling pathway contributes to oleanolic acid-induced liver injury

Oleanolic acid (OA) is a pentacyclic triterpenoid compound used clinically for acute and chronic hepatitis. However, high dose or long-term use of OA causes hepatotoxicity, which limits its clinical application. Hepatic Sirtuin (SIRT1) participates in the regulation of FXR signaling and maintains hepatic metabolic homeostasis. This study was designed to determine whether SIRT1/FXR signaling pathway contributes to the hepatotoxicity caused by OA. C57BL/6J mice were administered with OA for 4 consecutive days to induce hepatotoxicity. The results showed that OA suppressed the expression of FXR and its downstream targets CYP7A1, CYP8B1, BSEP and MRP2 at both mRNA and protein levels, breaking the homeostasis of bile acid leading to hepatotoxicity. However, treatment with FXR agonist GW4064 noticeably attenuated hepatotoxicity caused by OA. Furthermore, it was found that OA inhibited protein expression of SIRT1. Activation of SIRT1 by its agonist SRT1720 significantly improved OA-induced hepatotoxicity. Meanwhile, SRT1720 significantly reduced the inhibition of protein expression of FXR and FXR-downstream proteins. These results suggested that OA may cause hepatotoxicity through SIRT1 dependent suppression of FXR signaling pathway. In vitro experiments confirmed that OA suppressed protein expressions of FXR and its targets through inhibition of SIRT1. It was further revealed that silencing of HNF1α with siRNA significantly weakened regulatory effects of SIRT1 on the expression of FXR as well as its target genes. In conclusion, our study reveals that SIRT1/FXR pathway is crucial in OA-induced hepatotoxicity. Activation of SIRT1/HNF1α/FXR axis may represent a novel therapeutic target for ameliorating OA and other herb-induced hepatotoxicity.

Effect directed analysis of bioactive compounds in leaf extracts from two Salvia species by High-performance thin-layer chromatography

Extracts of two Salvia species, Salvia apiana (white sage) and Salvia officinalis (common sage) were screened for phytoconstituents with the ability to act as antidiabetic, cognitive enhancing, or antimicrobial agents, by hyphenation of high-performance thin-layer chromatography with enzymatic and microbial effect directed assays. Two bioactive zones with α-amylase inhibition (zone 1 and zone 2), 3 zones for acetylcholinesterase inhibition (zones 3, 4 and 5), and two zones for antimicrobial activity (zones 4 and 5) were detected. The compounds from the five bioactive zones were initially identified by coelution with standards and comparing the R_F values of standards to the bioautograms. Identity was confirmed with ATR-FTIR spectra of the isolated compounds from the bioactive zones. A significantly higher α-amylase and acetylcholinesterase inhibition of S. apiana leaf extract was associated with a higher flavonoid and diterpenoid content. Fermented S. officinalis extract exhibited a significantly higher ability to inhibit α-amylase compared to other non-fermented extracts from this species, due to increased extraction of flavonoids. The ATR-FTIR spectra of 2 zones with α-amylase inhibition, indicated that flavonoids and phenolic acids were responsible for α-amylase inhibition. Multiple zones of acetylcholinesterase inhibition were related to the presence of phenolic abietane diterpenoids and triterpenoid acids. The presence of abietane diterpenoids and triterpenoid acids was also found responsible for the mild antimicrobial activity. Flash chromatography was used to isolate sufficient amounts of bioactive compounds for further characterisation via NMR and MS spectroscopy. Five compounds were assigned to the zones where bioactivity was observed: cirsimaritin (zone 1), a caffeic acid polymer (zone 2), 16-hydroxyrosmanol (zone 3), 16-hydroxycarnosic acid (zone 4), oleanolic and ursolic acids (zone 5).

Mechanism of epithelial-mesenchymal transition in cancer and its regulation by natural compounds

Epithelial-mesenchymal transition (EMT) is a complex process with a primordial role in cellular transformation whereby an epithelial cell transforms and acquires a mesenchymal phenotype. This transformation plays a pivotal role in tumor progression and self-renewal, and exacerbates resistance to apoptosis and chemotherapy. EMT can be initiated and promoted by deregulated oncogenic signaling pathways, hypoxia, and cells in the tumor microenvironment, resulting in a loss-of-epithelial cell polarity, cell-cell adhesion, and enhanced invasive/migratory properties. Numerous transcriptional regulators, such as Snail, Slug, Twist, and ZEB1/ZEB2 induce EMT through the downregulation of epithelial markers and gain-of-expression of the mesenchymal markers. Additionally, signaling cascades such as Wnt/β-catenin, Notch, Sonic hedgehog, nuclear factor kappa B, receptor tyrosine kinases, PI3K/AKT/mTOR, Hippo, and transforming growth factor-β pathways regulate EMT whereas they are often deregulated in cancers leading to aberrant EMT. Furthermore, noncoding RNAs, tumor-derived exosomes, and epigenetic alterations are also involved in the modulation of EMT. Therefore, the regulation of EMT is a vital strategy to control the aggressive metastatic characteristics of tumor cells. Despite the vast amount of preclinical data on EMT in cancer progression, there is a lack of clinical translation at the therapeutic level. In this review, we have discussed thoroughly the role of the aforementioned transcription factors, noncoding RNAs (microRNAs, long noncoding RNA, circular RNA), signaling pathways, epigenetic modifications, and tumor-derived exosomes in the regulation of EMT in cancers. We have also emphasized the contribution of EMT to drug resistance and possible therapeutic interventions using plant-derived natural products, their semi-synthetic derivatives, and nano-formulations that are described as promising EMT blockers.

Analysis of A Major Metabolite of Ursolic Acid— Ursolic Acid Sulfate, and Its Quantitative Determination on LC/MS in Human Liver Homogenate

Ursolic acid (UA) is a naturally occurring pentacyclic triterpenoid that exhibits extensive pre-systemic metabolism from in vitro studies. However, there are no available authentic metabolite standards or validated analytical methods to quantitate UA metabolites. We have identified ursolic acid sulfate (UAS) as one of the major metabolites. We were able to identify and characterize its structure via comparison to the chemically synthesized UAS. A cyano (CN, 150 × 4.6 mm, 5 µm) column along with a gradient elution of acetonitrile and 0.08% (v/v) acetic acid, pH 3.0 were employed for chromatographic separation. Negative single ion recording mode (SIR) with electron-spray ionization (ESI) source at mass-to-charge ratios of 455.3 and 535.3 were monitored for UA and UAS, respectively. UAS linearity range was 0.010-2.500 µM. The absolute values of intra-day and inter-day precision (CV, %) and accuracy (DFN, %) were all below 15%. Thus, the analytical method has been validated in the human subcellular fractions to facilitate in vitro/ in vivo DMPK and future clinical disposition studies on UA.

Health functions and related molecular mechanisms of Miconia genus: A systematic review

The Miconia genus is traditionally used in folk medicine in Brazil and other tropical American countries and is represented by 282 species in this region. It is a multifaceted genus of medicinal plants widely used to treat rheumatoid arthritis (RA), pain, inflammatory diseases, and many more therapeutic applications. In the present study, we systematically identify and discuss the literature on in vivo and in vitro studies focusing on the therapeutic potentials and related molecular mechanisms of the Miconia genus. The review also assessed phytochemicals and their pharmacological properties and considered safety concerns related to the genus. Literature searches to identify studies on the Miconia genus were carried out through four main electronic databases, namely PubMed, Embase, Scopus, and Web of Science limited to Medical Subjects Headings (MeSH) and Descriptores en Ciencias de la Salud (DCS) (Health Sciences Descriptors) to identify studies published up to December 2022. The relevant information about the genus was gathered using the keywords 'Miconia', 'biological activities', 'therapeutic mechanisms', 'animal model, 'cell-line model', 'antinociceptive', 'hyperalgesia', 'anti-inflammatory', and 'inflammation'. The therapeutic potentials and mechanisms of action of 14 species from genus Miconia were examined in 18 in vitro studies and included their anti-inflammatory, anticancer, analgesic, antibacterial, cytotoxic, mutagenic, antioxidant, anti-leishmanial, antinociceptive, schistosomicidal, and anti-osteoarthritis potentials, and in eight in vivo studies, assessing their analgesic, antioxidant, antinociceptive, and anti-osteoarthritis activities. Some of the main related molecular mechanisms identified are the modulation of cytokines such as IL-1β, IL-6, and TNF-α, as well as the inhibition of inflammatory mediators and prostaglandin synthesis. The limited number of studies showed that commonly available species from the genus Miconia are safe for consumption. Miconia albicans Sw.Triana and Miconia rubiginosa (Bonpl.) DC was the most frequently used species and showed significant efficacy and potential for developing safe drugs to treat pain and inflammation.

A color-change fluorescence sensor for oleanolic acid based on chiral camphanic decorated bis-cyanostilbene

Although various fluorescent sensors for biomolecules had been extensively reported, the effective fluorescent sensor was seldom reported for detecting oleanolic acid up to now. This work reports the first color-change fluorescence sensor for oleanolic acid based on a bridging bis-cyanostilbene derivative with chiral camphanic groups (C-BCS). C-BCS possessed the chartreuse fluorescence in aqueous media, which transferred to strong blue fluorescence in the presence of oleanolic acid. This sensing ability of C-BCS for oleanolic acid exhibited the high selectivity among all kinds of biomolecules and ions. The good linearity between the fluorescence intensity and concentration of oleanolic acid was acquired in the range of 0.2 × 10^-6 to 8.0 × 10^-6 M with the detecting limitation of 0.0582 μM. The 1:1 binding process was clarified as oleanolic acid located in the opening cavity composed of two bridging cyanostilbene units and two chiral camphanic groups based on multiple hydrogen bonds and hydrophobic interaction. The detecting ability of C-BCS was applied on sensing oleanolic acid in thin-layer chromatography analysis, imprinting experiment, tap water, and tea samples, suggesting the effective on-site sensing abilities of C-BCS for oleanolic acid in real samples and daily life.

Ursolic acid enhances the effect of exercise training on vascular aging by reducing oxidative stress in aged type 2 diabetic rats

Ursolic acid (UA) mediates the vasorelaxant activity via nitric oxide (NO) release, and upregulation of endothelial nitric oxide synthase (eNOS) in endothelial cells (ECs) in disease conditions with increased oxidative stress (OS). The present study aimed to reflect on the impact of 8 weeks of a combination of UA supplementation and resistance/endurance training in old male Wistar rats having a high-fat diet and/or low-dose streptozotocin-induced type 2 diabetes (HFD/STZ-induced T2D), with an emphasis on Sirtuin 1 (SIRT1)-endothelial nitric oxide synthase (eNOS) axis and OS indices in their aortic tissues. A total number of56 21-month-old male Wistar rats with HFD/STZ-induced T2D were randomized into seven groups (n = eight animals per group): (1) sedentary old nondiabetic (Control [C]); (2) sedentary HFD/STZ-induced T2D (Diabetic [D]); (3) sedentary HFD/STZ-induced T2D plus UA (Diabetic + Ursolic Acid [DU]); (4) endurance-trained HFD/STZ-induced T2D (Diabetic + Endurance Training [DE]); (5) resistance-trained HFD/STZ-induced T2D (Diabetic + Resistance Training [DR]); (6) endurance-trained HFD/STZ-induced T2D plus UA (Diabetic + Endurance Training + Ursolic Acid [DEU]); and (7) resistance-trained STZ-diabetic plus UA (Diabetic + Resistance Training + Ursolic Acid [DRU]) rats. The ladder-based resistance training group performed the ladder resistance training at 60% of the maximum voluntary carrying capacity (MVCC), 14-20 climbs in each session, with a one-min rest between each two trials, 5 days a week. The treadmill-based endurance exercise training protocol consisted of repeated bouts of high- and low-intensity training with 60-75% maximal running speed and 30%-40% maximal running speed in the course of 8 weeks, respectively. The animals in the supplement groups also took 500 mg of UA/kg of high-fat diet/day, resulting in a daily UA intake of approximately 250 mg UA per kg of body weight rat/day. The resistance/endurance training plus the UA consumption could partially reverse the levels of malondialdehyde (MDA), nitric oxide (NO), as well as total antioxidant capacity (TAC). It was concluded that oral 0.5% UA supplementation can prevent vascular aging biomarkers in a HFD/STZ-induced T2D model. Further studies are also required to clarify how chronic consumption of UA with/without training protocols reverses vascular aging process.

Synthesis and Biological Evaluation of Substituted Pyrazole-Fused Oleanolic Acid Derivatives as Novel Selective α-Glucosidase Inhibitors

A series of novel substituted pyrazole-fused oleanolic acid derivative were synthesized and evaluated as selective α-glucosidase inhibitors. Among these analogs, compounds 4a-4f exhibited more potent inhibitory activities compared with their methyl ester derivatives, and standard drugs acarbose and miglitol as well. Besides, all these analogs exhibited good selectivity towards α-glucosidase over α-amylase. Analog 4d showed potent inhibitory activity against α-glucosidase (IC₅₀ =2.64±0.13 μM), and greater selectivity towards α-glucosidase than α-amylase by ∼33-fold. Inhibition kinetics showed that compound 4d was a non-competitive α-glucosidase inhibitor, which was consistent with the result of its simulation molecular docking. Moreover, the in vitro cytotoxicity of compounds 4a-4f towards hepatic LO2 and HepG2 cells was tested.