Biosynthesis of copper nanoparticles using Alstonia scholaris leaves and its antimicrobial studies.

The utilization of plants for the production of metallic nanoparticles is gaining significant attention in research. In this study, we conducted phytochemical screening of Alstonia scholaris (A. scholaris) leaves extracts using various solvents, including chloroform, ethyl acetate, n-hexane, methanol, and water. Our findings revealed higher proportions of flavonoids and alkaloids in both solvents compared to other phytochemical species. In the methanol, extract proteins, anthraquinone and reducing sugar were not detected. On the other hand, the aqueous extract demonstrated the presence of amino acids, reducing sugar, phenolic compounds, anthraquinone, and saponins. Notably, ethyl acetate and chloroform extracts displayed the highest levels of bioactive compounds among all solvents. Intrigued by these results, we proceeded to investigate the antibacterial properties of the leaf extracts against two major bacterial strains, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). All extracts exhibited significant zones of inhibition against both bacterial isolates, with S. aureus showing higher susceptibility compared to E. coli. Notably, the methanol extract displayed the most potent I hibitory effect against all organisms. Inspired by the bioactivity of the methanol extract, we employed it as a plant-based material for the green synthesis of copper nanoparticles (Cu-NPs). The synthesized Cu-NPs were characterized using Fourier infrared spectroscopy (FT-IR), UV-visible spectroscopic analysis, and scanning electron microscopy (SEM). The observed color changes confirmed the successful formation of Cu-NPs, while the FTIR analysis matched previously reported peaks, further verifying the synthesis. The SEM micrographs indicated the irregular shapes of the surface particles. From the result obtained by energy dispersive X-ray spectroscopic analysis, Cu has the highest relative abundance of 67.41 wt%. Confirming the purity of the Cu-NPs colloid. These findings contribute to the growing field of eco-friendly nanotechnology and emphasize the significance of plant-mediated approaches in nanomaterial synthesis and biomedical applications.

Alstoboonine, an Ulean-Type Indole Alkaloid from Alstonia boonei Leaves.

Alstonia boonei De Wild is a common plant in West Africa used in traditional medicine for various indications. While the stem bark has frequently been investigated, not much is known about the phytochemistry and bioactivity of the leaves. Within the current study, the major alkaloids of a hydroethanolic leaf extract were therefore isolated and characterized by MS, NMR, and ECD. This led to the identification of alstoboonine 1, a new ulean-type alkaloid, along with eight previously reported indole alkaloids, 15-hydroxyangustilobine A (2), 6,7-seco-angustilobine B (3), 6,7-seco-19,20-α-epoxyangustilobine B (4), alstrostine E (5), alstrostine C (6), alstrostine D (7), 12-methoxyechitamidine (8), and 19-oxo-12-methoxyechitamidine (9). 1 was moderately active in vitro against Plasmodium falciparum NF54 (IC50 6.9 µM), but inactive against other protozoan parasites (Trypanosoma brucei, Trypanosoma cruzi, Leishmania donovani). No significant cytotoxic effects were observed in L6 rat skeletal myoblast cells and MCF-7 breast cancer cells. Similarly, compounds 3 to 9 did not show cytotoxicity in MCF-7 cells. Due to the reported traditional use of the plant as an anthelmintic, the major alkaloids 2, 5, 6, and 8 were tested against the nematode Caenorhabditis elegans. Nematicidal effects were observed for 6 (LC50 400 µM), whereas 2, 5, and 8 were inactive.

Antispasmodic Effect of Alstonia boonei De Wild. and Its Constituents: Ex Vivo and In Silico Approaches.

BACKGROUND: Alstonia boonei, belonging to the family Apocynaceae, is one of the best-known medicinal plants in Africa and Asia. Stem back preparations are traditionally used as muscle relaxants. This study investigated the antispasmodic properties of Alstonia boonei Stem back and its constituents. METHOD: The freeze-dried aqueous Stem back extract of A. boonei, as well as dichloromethane (DCM), ethyl acetate, and aqueous fractions, were evaluated for their antispasmodic effect via the ex vivo method. Two compounds were isolated from the DCM fraction using chromatographic techniques, and their antispasmodic activity was evaluated. An in silico study was conducted by evaluating the interaction of isolated compounds with human PPARgamma-LBD and human carbonic anhydrase isozyme. RESULTS: The Stem back crude extract, DCM, ethyl acetate, and aqueous fractions showed antispasmodic activity on high-potassium-induced (K+ 80 mM) contractions on isolated rat ileum with IC50 values of 0.03 ± 0.20, 0.02 ± 0.05, 0.03 ± 0.14, and 0.90 ± 0.06 mg/mL, respectively. The isolated compounds from the DCM fraction were ß-amyrin and boonein, with only boonein exhibiting antispasmodic activity on both high-potassium-induced (IC50 = 0.09 ± 0.01 µg/mL) and spontaneous (0.29 ± 0.05 µg/mL) contractions. However, ß-amyrin had a stronger interaction with the two proteins during the simulation. CONCLUSION: The isolated compounds boonein and ß-amyrin could serve as starting materials for the development of antispasmodic drugs.

Phytochemical analysis, in vitro and in silico effects from Alstonia boonei De Wild stem bark on selected digestive enzymes and adipogenesis in 3T3-L1 preadipocytes.

BACKGROUND: Obesity is a global health issue arising from the unhealthy accumulation of fat. Medicinal plants such as Alstonia boonei stem bark has been reported to possess body weight reducing effect in obese rats. Thus, this study sought to investigate the in vitro and in silico effects of fractions from Alstonia boonei stem bark on selected obesity-related digestive enzymes and adipogenesis in 3T3-L1 preadipocytes. METHOD: Two fractions were prepared from A. boonei: crude alkaloid fraction (CAF) and crude saponin fraction (CSF), and their phytochemical compounds were profiled using Liquid chromatography with tandem mass spectrometry (LCMS/MS). The fractions were assayed for inhibitory activity against lipase, α-amylase and α-glucosidase, likewise their antiadipogenic effect in 3T3-L1 adipocytes. The binding properties with the 3 enzymes were also assessed using in silico tools. RESULTS: Eleven alkaloids and six saponin phytochemical compounds were identified in the CAF and CSF using LCMS/MS. The CAF and CSF revealed good inhibitory activity against pancreatic lipase enzyme, but weak and good activity against amylase respectively while only CSF had inhibitory activity against α-glucosidase. Both fractions showed antiadipogenic effect in the clearance of adipocytes and reduction of lipid content in 3T3-L1 adipocytes. The LCMS/MS identified compounds (41) from both fractions demonstrated good binding properties with the 3 enzymes, with at least the top ten compounds having higher binding energies than the reference inhibitors (acarbose and orlistat). The best two docked compounds to the three enzymes were firmly anchored in the substrate binding pockets of the enzymes. In a similar binding pattern as the reference acarbose, Estradiol-17-phenylpropionate (-11.0 kcal/mol) and 3α-O-trans-Feruloyl-2 α -hydroxy-12-ursen-28-oic acid (-10.0 kcal/mol) interacted with Asp197 a catalytic nucleophile of pancreatic amylase. Estradiol-17-phenylpropionate (-10.8 kcal/mol) and 10-Hydroxyyohimbine (-10.4 kcal/mol) interacted with the catalytic triad (Ser152-Asp176-His263) of pancreatic lipase while Estradiol-17-phenylpropionate (-10.1 kcal/mol) and 10-Hydroxyyohimbine (-9.9 kcal/mol) interacted with Asp616 and Asp518 the acid/base and nucleophilic residues of modelled α-glucosidase. CONCLUSION: The antiobesity effect of A. boonei was displayed by both the alkaloid and saponin fractions of the plant via inhibition of pancreatic lipase and adipogenesis.

Monoterpene indole alkaloids from the roots of Alstonia rupestris and their anti-inflammatory activity.

Four new monoterpene indole alkaloids (1-4) together with twelve known alkaloids (5-16) were isolated from the roots of Alstonia rupestris. Compound 1 was the first example of C2-symmetric heteroyohimbine-type indole alkaloid homodimer obtained from natural plant resource. Their structures were elucidated on the basis of spectroscopic data. The absolute configuration of 1 was determined by comparison of its calculated and experimental electronic circular dichroism (ECD) spectra. All compounds were evaluated for their anti-inflammatory activities by measuring their NO inhibitory effects in LPS-stimulated RAW 264.7 cells. Compound 2 showed strong NO inhibition with IC50 value of 4.2 ± 1.3 µM. Moreover, compound 2 could decrease the expressions of cyclooxygenase-2 (COX-2) and transforming growth factor beta-1 (TGF-ß1).

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 19­epi-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.

Neuroprotection by Alstonia boonei De Wild., Anacardium occidentale L., Azadirachta indica A.Juss. and Mangifera indica L.

ETHNOPHARMACOLOGY RELEVANCE: Alstonia boonei De Wild. (stem bark), Anacardium occidentale L. (stem bark), Azadirachta indica A.Juss (leaves), Enantia chlorantha Oliv. (stem bark), Khaya senegalensis A.Juss (stem bark) Mangifera indica L. (stem bark), and Nauclea latifolia Sm. (stem bark) are used for treating malaria in southwest Nigeria. Surveys revealed that these plants are also employed for treating symptoms of malaria and cerebral malaria in the region. AIM OF THE STUDY: In this study, the effects of freeze-dried extracts of these plants were investigated on synthetic hemozoin (HZ)-induced neuroinflammation, neuronal damage, and increased permeability of brain microvascular endothelial cells. MATERIALS AND METHODS: Effects of freeze-dried plant extracts were investigated on neuroinflammation by measuring levels of pro-inflammatory mediators in culture supernatants, while in-cell western assays were used to measure protein levels of iNOS and NLRP3. Effects on HZ-induced neurotoxicity and ROS generation was measured using MTT and DCFDA assays, respectively. HZ-induced permeability of hCMEC/D3 endothelial cells was determined using the in vitro vascular permeability assay kit. RESULTS: The extracts produced significant (p < 0.05) reduction in TNFα, IL-6, IL-1ß, MCP-1, RANTES and iNOS/NO production in HZ-stimulated BV-2 microglia. Pre-treatment with 50 µg/mL of A. boonei, A. indica, A. occidentale, E. chlorantha and M. indica also resulted in the inhibition of NF-κB activation. Pre-treatment with A. indica produced, A. occidentale, M. indica and A. boonei reduced HZ-induced increased NLRP3 protein expression. HZ-induced increased caspase-1 activity was also reduced by A. boonei, A. occidentale, A. indica, E. chlorantha, and M. indica. Freeze-dried extracts of A. boonei, A. occidentale, A. indica and M. indica produced neuroprotective effect in HT-22 neuronal cells incubated with HZ by preventing HZ-induced neurotoxicity, ROS generation, DNA fragmentation and caspase 3/7 activity. Inhibition of HZ-induced increase in permeability of human hCMEC/D3 brain endothelial cells was also observed with A. boonei, A. occidentale, A. indica and M. indica, while reducing the release of TNFα and MMP-9. CONCLUSIONS: These results suggest that A. boonei, A. occidentale, A. indica and M. indica are neuroprotective through inhibition of neuroinflammation, neuronal damage and increased permeability of blood brain barrier. The outcome of the study provides pharmacological evidence for the potential benefits of plants as herbal treatments for cerebral malaria symptoms.

Significant anti-inflammatory aziridine-containing indole alkaloids from the Chinese medicinal plant Alstonia scholaris.

Two unique windmill-like aziridine-containing indole alkaloids, possessing an unprecedented 6/5/5/6/6/5/3 rigid ring system and an unusual azabicyclo[3.1.0]hexane core, were isolated from Alstonia scholaris. Their structures were established by spectroscopy, X-ray diffraction, and electronic circular dichroism calculations. The novel compounds exhibited significant anti-inflammatory bioactivity in vitro and alleviated LPS-induced acute lung injury in mice.

Butanol fraction of Alstonia boonei De Wild. leaves ameliorate oxidative stress and modulate key hypoglycaemic processes in diabetic rats.

OBJECTIVE: The effect of Alstonia boonei fractions on glucose homeostasis was investigated via in vitro enzyme inhibition activity, ex vivo glucose uptake assay, and in vivo methods in diabetic rats. METHODOLOGY: A. boonei fractions were subjected to in vitro α-glucosidase inhibitory assay and then ex vivo glucose uptake activity. The butanol fraction of the leaves (ABBF) was picked for the in vivo assay since it showed more activity in the initial tests conducted. ABBF was administrated via oral dosing to six-weeks old fructose-fed STZ-induced type 2 diabetic rats over a 5-week experimental period. RESULTS: ABBF treatment at a low dose of 150 mg/kg bw, significantly (p < .05) reduced blood glucose level, enhanced oral glucose tolerance ability, restored insulin secretion and hepatic glycogen synthesis as well as promoted islet regeneration than the high dose (300 mg/kg bw). CONCLUSION: These results suggest that ABBF could be exploited as a therapeutic potential for treating T2D.

Anti-Helicobacter pylori, anti-Inflammatory, and Antioxidant Activities of Trunk Bark of Alstonia boonei (Apocynaceae).

An ulcer is an erosion of the gastric mucosa that occurs following an imbalance between the aggression and protective factors and/or an infection with Helicobacter pylori (H. pylori). About 90-100% of duodenal ulcers and 70-80% of gastric ulcers are caused by H. pylori. The objective of this work was to evaluate in vitro the anti-H. pylori activity and then the anti-inflammatory and antioxidant properties of aqueous and methanol extracts of Alstonia boonei. The anti-H. pylori tests (CMI and antiureasic activity) were determined using the agar well diffusion method, the microbroth dilution method, and the measurement of ammonia production by the indophenol method; the anti-inflammatory properties were evaluated by inhibition of proteinases, denaturation of albumin, production of NO by macrophages, cell viability, and hemolysis of red blood cells by heat; then, the antioxidant properties were evaluated by the FRAP method (ferric reducing antioxidant power) and the DPPH (1,1-diphenyl-2-picrylhydrazyl) test. The results show that the best trapping of the DPPH radical was obtained with the methanol extract (EC50 = 8.91 µg/mL) compared to the aqueous extract (EC50 = 19.86 µg/mL). The methanol extract also showed greater iron-reducing activity than the aqueous extract and vitamin C. Furthermore, at the concentration of 200 µg/mL, the methanol extract showed a percentage (96.34%) strains of H. pylori higher than that of the aqueous extract (88.52%). The MIC90 of the methanol extract was lower than that of the aqueous extract. The methanol extract showed a higher percentage inhibition (85%) of urease than the aqueous extract (73%). The methanol extract at a concentration of 1000 µg/mL showed the greatest ability to inhibit proteinase activity, albumin denaturation, and red blood cell hemolysis; on the other hand, maximum cell viability and greater production of nitrite oxide by macrophages were obtained with the aqueous extract. Aqueous and methanol extracts of Alstonia boonei possess anti-H. pylori which would probably be linked to their antioxidant and anti-inflammatory properties.

New phenylpropanoids and monoterpene alkaloids with vasorelaxant activities from the branches of Alstonia scholaris.

Two new phenylpropanoids (1-2), one new nor-monoterpenoid alkaloid (3), one new monoterpene alkaloid (4), together with nine known compounds (5-13) were obtained from the branches of Alstonia scholaris. The structures of the undescribed compounds were determined by extensive spectroscopic analysis. Alkaloid 3 represented the first example of C-4 methylated nor-monoterpenoid alkaloids. A possible biosynthetic pathway for this new type of monoterpene alkaloids was proposed. All the isolates were evaluated for vasorelaxant activity against phenylephrine-induced contraction of rat mesenteric arteries. Compounds 1, 4, 9, 12, and 13 showed significant vasorelaxant activity with relaxation rates above 90% at 200 µM and exhibited moderate vasorelaxant activity with IC50 values ranging from 41.87 to 93.30 µM by further studies. It was the first report on the potential vasorelaxant activity of monoterpene alkaloids. Monoterpene alkaloids 3 and 4 may be served as the potential lead compounds for the discovery of vasodilators, due to their simple and optimizable structures.

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

ETHNOPHARMACOLOGY RELEVANCE: One folk use of Alstonia scholaris (L.) R. Br. in "Dai" ethno-medicine system is to treat gouty arthritis, which might be caused by hyperuricemia, but anti-hyperuricemic investigation of A. scholaris were rarely reported. AIM OF THE STUDY: To verify anti-hyperuricemic property of A. scholaris, and explore its bioactive compounds in vivo and in vitro. MATERIALS AND METHODS: The anti-hyperuricemic bioactivity of the non-alkaloids fraction and compounds were evaluated with potassium oxonate (PO) induced hyperuricemia mice model in vivo, and monosodium urate (MSU) induced human renal tubular epithelial cells (HK-2) was selected to test in vitro, respectively, with benzobromarone as the positive control. 11 triterpenoids were isolated by phytochemical methods and their structures were elucidated by spectroscopic analysis and ECD calculation. RESULTS: The non-alkaloids fraction of A. scholaris decreased the serum uric acid (UA) level in mice model significantly at the doses of 100 mg/kg and 200 mg/kg, and then nine ursane- and two oleanane-triterpenoids including four new compounds (1-3 and 10) were isolated from the bioactive fraction, in which compounds 1, 4, 5, 6 and 10 exhibited better anti-hyperuricemic tendency in vitro by promoting the excretion of UA in MSU-induced HK-2 cell model at a concentration of 5 µM. Furthermore, compounds 1 and 4 were proved to reduce the serum UA level in mice significantly at 5 mg/kg in vivo. CONCLUSIONS: The results supported the traditional use of A. scholaris in treating gouty arthritis, and also provided new bioactive triterpenoids for further chemical and pharmacological investigation.

Therapeutic potential of indole alkaloids in respiratory diseases: A comprehensive review.

BACKGROUND: Indole alkaloids are very promising for potential therapeutic purposes and appear to be particularly effective against respiratory diseases. Several experimental studies have been performed, both in vivo and in vitro, to evaluate the effectiveness of indole alkaloids for the management of respiratory disorders, including asthma, emphysema, tuberculosis, cancer, and pulmonary fibrosis. PURPOSE: The fundamental objective of this review was to summarize the in-depth therapeutic potential of indole alkaloids against various respiratory disorders. STUDY DESIGN: In addition to describing the therapeutic potential, this review also evaluates the toxicity of these alkaloids, which have been utilized for therapeutic benefits but have demonstrated toxic consequences. Some indole alkaloids, including scholaricine, 19-epischolaricine, vallesamine, and picrinine, which are derived from the plant Alstonia scholaris, have shown toxic effects in non-rodent models. METHODS: This review also discusses clinical studies exploring the therapeutic efficacy of indole alkaloids, which have confirmed the promising benefits observed in vivo and in vitro. RESULTS: The indole alkaloidal compounds have shown efficacy in subjects with respiratory diseases. CONCLUSION: The available data established both preclinical and clinical studies confirm the potential of indole alkaloids to treat the respiratory disorders.

Development and validation of a new HPTLC-HRMS method for the quantification of a potent pancreatic lipase inhibitory lead Echitamine from Alstonia scholaris.

Alstonia scholaris is an important indole alkaloid rich medicinal plant with diverse pharmacological activity. To understand the effect of extraction techniques, the stem bark sample of A. scholaris was subjected to continuous hot percolation, ultrasonic extraction, and cold maceration techniques. Continuous hot percolation technique extractive exhibited a potential pancreatic lipase (PL) inhibitory activity and further bio-assay guided fractionation resulted in the isolation of echitamine with a PL inhibitory activity (IC50 = 10.92 µM). A new validated HPTLC-HRMS method was developed for the quantification of echitamine by using a mobile phase of chloroform: methanol (80:20, v/v) with 0.04% formic acid. Echitamine content in the individual extractives were in direct correlation with the PL inhibitory activity (Pearson's r = -0.9409). The molecular docking studies further confirmed the PL inhibitory potential of echitamine. These results clearly highlight the role of echitamine as a natural product-based lead for potent PL inhibitory activity.

In vitro screening of plant extracts traditionally used as cancer remedies in Ghana - 15-Hydroxyangustilobine A as the active principle in Alstonia boonei leaves.

ETHNOPHARMACOLOGICAL RELEVANCE: Cancer represents a major health burden and drain on the global healthcare systems. Traditional African medicine widely use a variety of plant species for treatment of different kinds of cancer. A previous systematic survey by traditional healers in the Ashanti region of Ghana revealed a good overview on the plant species and herbal materials used for the different types of cancer. AIMS OF THE STUDY: The following study aimed to investigate 18 herbal materials from 10 plant species based on the cancer survey in Ghana regarding potential cytotoxicity against different cancer cell lines under in vitro conditions followed by subsequent bioassay-guided fractionation towards the active principle. MATERIALS AND METHODS: Ethanol-water (1:1) extracts were tested (1-100 µg/mL) against a panel of cancer cell lines according to their respective traditional use. Selected extracts with relevant cytotoxicity in this screening were also tested against common pediatric malignancies (leukemias (HL-60, REH) and Ewing sarcoma (RD-ES and CADO-ES1)). Bioassay-guided fractionation of the hydroalcoholic extract from Alstonia boonei was performed by liquid-liquid chromatography and preparative HPLC. Preliminary mechanistic studies on the mode of action were performed by flow cytometric cell cycle analysis as well as apoptosis and necrosis staining. RESULTS: Screening of plant extracts revealed relevant cytotoxicity against all tested cancer cell lines for Alstonia boonei leaves and stem of Paulinia pinnata. The A. boonei extract was additionally found to be active against common pediatric tumor types (leukemias and Ewing sarcoma). Bioassay-guided fractionation of the A. boonei extract revealed the presence of 15-hydroxyangustilobine A 1 as the active principle (IC50 26 µM against MCF-7 cells). This is the first report of this compound in A. boonei. 1 was shown to lead to cell cycle arrest in the G2/M-phase (MCF-7 cells), triggering cells at least partially into apoptosis. CONCLUSION: In summary, an appreciable in vitro activity was revealed for the leaf extract from A. boonei and the isolated vallesamine type indole alkaloid 1, which has to be investigated in future studies towards a potential clinical use.

Pharmacological effects of indole alkaloids from Alstonia scholaris (L.) R. Br. on pulmonary fibrosis in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Alstonia scholaris (L.) R. Br. (Apocynaceae) is a Dai folk medicine for the treatment of lung diseases in China. AIM OF THE STUDY: The present study investigated the anti-pulmonary fibrosis effects of total alkaloids (TA) and the potential active ingredients and its possible mechanism. MATERIALS AND METHODS: After intratracheal instillation of bleomycin (BLM, 5 mg/kg), mice were divided into ten groups, and orally treated with the corresponding samples once daily for 28 days. The effect of indole alkaloids was determined through analysis of cytokines, as well as histopathological examinations and gene expressions. RESULTS: Severe lung fibrosis was observed in the BLM-treated mice on day 28. However, the administration of TA significantly ameliorated the pathological changes in the lungs, decreased the content of Krebs von den Lungen-6, lactate dehydrogenase, transforming growth factor-ß (TGF-ß), hydroxyproline, type I collagen, and malonaldehyde, and enhanced the activity of superoxide dismutase in the serum and lung tissues. In addition, the enhanced TGF-ß and matrix metalloproteinase-1 (MMP-1) expressions in BLM-induced mice were obviously weakened by indole alkaloids, as well as the ratio of matrix metalloproteinase-1 to tissue inhibitor of metalloproteinase-1 was decreased. Moreover, picrinine and scholaricine yielded markedly better values in the aforementioned indices than those in other samples, indicating that they may be the active ingredients of alkaloids. CONCLUSIONS: TA exerted protective effects against BLM-induced pulmonary fibrosis by reducing collagen deposition through TGF-ß/MMP-1 pathway.

Pharmacological insights and prediction of lead bioactive isolates of Dita bark through experimental and computer-aided mechanism.

Dita bark (Alstonia scholaris (L.) R. Br.) is an ethnomedicine used for the management of various ailments. This study aimed to investigate the biological properties of methanol extract of A. scholaris bark (MEAS), through in vivo, in vitro and in silico approaches alongside its phytochemical profiling. Identification and nature of the bioactive secondary metabolites were studied by the established qualitative tests and GC-MS analysis. The antidepressant activity was determined by forced swimming test (FST) and tail suspension test (TST) in mice. The anti-inflammatory and thrombolytic effect was evaluated using inhibition of protein denaturation technique and clot lysis technique, respectively. Besides, computational studies of the isolated compounds and ADME/T analysis were performed by Schrödinger-Maestro (v11.1) software, and PASS prediction was conducted through PASS online tools. The GC-MS analysis revealed the presence of several secondary metabolites in MEAS. Treatment with MEAS revealed a significant reduction of immobility time in a dose-dependent manner in FST and TST. Besides, MEAS showed substantial anti-inflammatory effects at the higher dose (400 µg/mL) as well as revealed notable clot lysis effect as compared to control. In the case of computer-aided investigation, all compounds meet the condition of Lipinski's rule of five. PASS study also predicted for all compounds, and among these safe compound furazan-3-amine showed the most spontaneous binding energy for both antidepressant and thrombolytic activities, as well as 5-dimethylamino-6 azauracil, found promising for anti-inflammatory activity. Taken together, the investigation concludes that MEAS can be a potent source of antidepressant, anti-inflammatory, and thrombolytic agents.

Total alkaloids from Alstonia scholaris inhibit influenza a virus replication and lung immunopathology by regulating the innate immune response.

BACKGROUND: Alstonia scholaris is a folk medicine used to treat cough, asthma and chronic obstructive pulmonary disease in China. Total alkaloids (TA) from A. scholaris exhibit anti-inflammatory properties in acute respiratory disease, which suggests their possible anti-inflammatory effect on influenza virus infection. PURPOSE: To assess the clinical use of TA by demonstrating their anti-influenza and anti-inflammatory effects and the possible mechanism underlying the effect of TA on influenza A virus (IAV) infection in vitro and to reveal the inhibitory effect of TA on lung immunopathology caused by IAV infection. METHODS: Antiviral and anti-inflammatory activities were assessed in Madin-Darby canine kidney (MDCK) and A549 cells and U937-derived macrophages infected with influenza A/PR/8/34 (H1N1) virus. Proinflammatory cytokine levels were measured by real-time quantitative PCR and Bio-Plex assays. The activation of innate immune signaling induced by H1N1 virus in the absence or presence of TA was detected in A549 cells by Western blot. Furthermore, mice were infected intranasally with H1N1 virus and treated with TA (50, 25 and 12.5 mg/kg/d) or oseltamivir (60 mg/kg/d) for 5 days in vivo. The survival rates and body weight were recorded, and the viral titer, proinflammatory cytokine levels, innate immune cell populations and histopathological changes in the lungs were analyzed. RESULTS: TA significantly inhibited viral replication in A549 cells and U937-derived macrophages and markedly reduced cytokine and chemokine production at the mRNA and protein levels. Furthermore, TA blocked the activation of pattern recognition receptor (PRR)- and IFN-activated signal transduction in A549 cells. Critically, TA also increased the survival rate, reduced the viral titer, suppressed proinflammatory cytokine production and innate immune cell infiltration and improved lung histopathology in a lethal PR8 mouse model. CONCLUSION: TA exhibits anti-viral and anti-inflammatory effects against IAV infection by interfering with PRR- and IFN-activated signal transduction.

Phytochemical screening of Alstonia venenata leaf and bark extracts and their antimicrobial activities.

Alstonia venenata is a plant commonly found in South India and used in traditional medicine. The aim of this study was to characterize the phytochemicals present in A. venenata leaf and bark extracts and study their antimicrobial activities. Solvent extractions with Soxhlet apparatus of leaves and bark were obtained using hexane, benzene, isopropanol, methanol, and water. The crude extracts were concentrated and screened for qualitative phytochemical content and analyzed by thin layer chromatography. The antibacterial, antifungal and antiviral activities of crude extracts were measured by in vitro methods. Alkaloids, carbohydrates, tannins, phenolic compounds, terpenoids, cardiac glycosides and amino acids were found in the different crude extracts analyzed. Isopropanol extracts showed antifungal activity and it was more pronounced in the bark extract than the leaf extract. Moreover, the isopropanol extract exhibited antibacterial and antiviral activity. In conclusion, the leaves and bark of A. venenata have antimicrobial components which are more present in the isopropanol fraction.

Phytochemical screening of Alstonia scholaris leaf and bark extracts and their antimicrobial activities.

Alstonia sholaris is an evergreen tree commonly found in South East Asia. In traditional medicine pharmacological activities are attributed to the leaves and bark of this plant. The aim of this study is characterizing the chemicals present in A. sholaris leaves and bark extracts and study their antimicrobial activities. Solvent extractions with Soxhlet apparatus of leaves and bark were obtained using hexane, benzene, isopropanol, methanol, and water. The crude extracts were concentrated and screened for qualitative phytochemical analysis and thin layer chromatography, and the antibacterial, antifungal an antiviral activity of crude extracts were measured by in vitro methods. Isopropanol and methanol extracts showed significant antibacterial activity and it was more pronounced against Gram positive than against Gram negative bacteria. Hexane, benzene, isopropanol and methanol fractions of A. scholaris bark and leaf showed activity against Enterobacter cloacae. Isopropanol extract showed maximum activity against selected human pathogenic fungus. In conclusion, the leaves and bark of A. scholaris are rich in phytochemicals with antimicrobial activities against human pathogens, being the isopropanol fraction the one with the highest antibacterial, antifungal, antiviral and anti-mycobacterial activities.