Phytochemicals of Salacia oblonga responsible for free radical scavenging and antiproliferative activity against breast cancer cell lines (MDA-MB-231)

In Vitro Hypoglycemic and Antioxidant Activities of Dichloromethane Extract of Xerophyta spekei

Diabetes mellitus is a chronic metabolic disorder which has greatly led to an increase in morbidity and mortality globally. Although Xerophyta spekei is widely used for the management of diabetes among the Embu and Mbeere communities in Kenya, it has never been empirically evaluated for its hypoglycemic activity. This study was carried out to verify the hypoglycemic activity of dichloromethane (DCM) extract of Xerophyta spekei as well as its antioxidant activity using various in vitro techniques. Phytochemicals associated with its antioxidant activity were identified through GC-MS. Data were subjected to descriptive statistics and expressed as mean ± standard error of the mean (X̄ ± SEM). Comparison between various variables was performed by using unpaired Student's t-test and one-way analysis of variance (ANOVA), followed by Tukey's post-hoc test. The confidence interval was set at 95%. The obtained results were presented in tables and graphs. Results showed that there was no difference in α-amylase inhibition activity between the plant extract and the standard (IC50 525.9 ± 12.34 and 475.1 ± 9.115, respectively; p  >  0.05). Besides, the glucose adsorption activity of the extract increased with an increase in glucose concentration (from 5.89 to 32.64 mg/dl at 5 mmol and 30 mmol of glucose, respectively; p  <  0.05). The extract also limited the diffusion of glucose more than the negative control (7.49 and 17.63 mg/dl, respectively; p  <  0.05). It also enhanced glucose uptake by yeast cells. In addition, the studied plant extract showed notable antioxidant activities. The therapeutic effects exhibited by this plant in managing diabetes mellitus and other ailments could be due to its antioxidant as well as its hypoglycemic activity. The study recommends the evaluation of X. spekei for in vivo hypoglycemic and antioxidant activities. Besides, the isolation of bioactive phytochemicals from the plant may lead to the development of new hypoglycaemic agents.

Cytoprotective remedies for ameliorating nephrotoxicity induced by renal oxidative stress

AIMS

Nephrotoxicity is the hallmark of anti-neoplastic drug metabolism that causes oxidative stress. External chemical agents and prescription drugs release copious amounts of free radicals originating from molecular oxidation and unless sustainably scavenged, they stimulate membrane lipid peroxidation and disruption of the host antioxidant mechanisms. This review aims to provide a comprehensive collection of potential cytoprotective remedies in surmounting the most difficult aspect of cancer therapy as well as preventing renal oxidative stress by other means.

MATERIALS AND METHODS

Over 400 published research and review articles spanning several decades were scrutinised to obtain the relevant data which is presented in 3 categories; sources, mechanisms, and mitigation of renal oxidative stress.

KEY-FINDINGS

Drug and chemical-induced nephrotoxicity commonly manifests as chronic or acute kidney disease, nephritis, nephrotic syndrome, and nephrosis. Renal replacement therapy requirements and mortalities from end-stage renal disease are set to rapidly increase in the next decade for which 43 different cytoprotective compounds which have the capability to suppress experimental nephrotoxicity are described.

SIGNIFICANCE

The renal system performs essential homeostatic functions that play a significant role in eliminating toxicants, and its accumulation and recurrence in nephric tissues results in tubular degeneration and subsequent renal impairment. Global statistics of the latest chronic kidney disease prevalence is 13.4 % while the end-stage kidney disease requiring renal replacement therapy is 4-7 million per annum. The remedial compounds discussed herein had proven efficacy against nephrotoxicity manifested consequent to impaired antioxidant mechanisms in preclinical models produced by renal oxidative stress activators.

Comparative synthesis and characterization of nanocomposites using chemical and green approaches including a comparison study on in vivo and in vitro biological properties

In this study, the anti-diabetic, anti-inflammatory, anti-cytotoxic, and antibacterial effects of various substances were studied in vitro. Malachite green's photocatalytic effects were used to determine the optimised sample while it was exposed to visible light. The intended nanocomposites were created without any contaminants, according to XRD data. The overall characterisation results of the green synthesis of CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(G)) were superior to those of the chemical synthesis of CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(C)). At the five doses examined, the green synthesis of CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(G)) and chemical synthesis of CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(C)) resulted in higher α-glucosidase inhibition percentages in the antidiabetic assay. HaCaT cells and MCF-7 cells were less harmful when treated with chemically synthesized CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(C)), and green synthesized CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(G)). From the results of the cytotoxicity tests against MCF-7 cells and HaCaT cells using the nanocomposites, the IC50 values of Salacia reticulata, green synthesized CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(G)), and chemically synthesized CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(C)) were calculated. This research work shows that the green synthesized CS/SiO2/TiO2/CeO2/Fe3O4 nanocomposites (CSTCF(G)) have strong anti-inflammatory, antibacterial and anti-diabetic properties, as well as considerable suppression of high activation in in vivo zebrafish embryo toxicity. The novelty of this study focused on the revelation that green synthesized nanocomposites are more affordable, environmentally friendly and biocompatible than chemically synthesized ones.

Antiviral COVID-19 protein and molecular docking: In silico characterization of various antiviral compounds extracted from Arisaema jacquemontii Blume

Arisaema jacquemontii Blume is a highly medicinal and poisonous plant belong to the family Araceae. It is used to treat several deadly diseases, including viral infections. It has antioxidant, anti-cancerous, antimalarial, anti-vermicidal, and antiviral activities. Therefore, five parts of the Arisaema jacquemontii Blume plant, such as leaf, seed, stem, pulp, and rhizome extract, were evaluated for metabolic and in silico characterization of probable compounds using gas chromatography-mass spectrometry (GC-MS) analysis. A total of 22 compounds were isolated from the methanolic extracts of A. jacquemontii Blume. A selected antiviral COVID-19 protein i.e., protease (6LU7) was docked against the obtained compounds. Different affinities were obtained through various compounds. The best results were shown by three different compounds identified in the rhizome. The maximum binding affinity of these compounds is 8.1 kJ/mol. Molecular docking (MD) indicate that these molecules have the highest binding energies and hydrogen bonding interactions. The binding mode of interaction was discovered to be reasonably effective for counteracting the SARS virus COVID-19. The findings of this study could be extremely useful in the development of more phytochemical-based COVID-19 therapeutics.

Antimicrobial Activities of Salacia oblonga Wall Leaf and Root Extracts Against Different Bacterial Strains and Fungal Isolates

Antibiotic resistance and the hazardous nature of synthetic drugs is threatening issue in the health sector. The alternative for this problem is to focus on plants that attribute to various compounds that exhibit therapeutic properties. Therefore, the study aims to evaluate the antimicrobial efficacy of Salacia oblonga leaf and root extracts against tested human pathogens. The S. oblonga extracts showed a significant zone of inhibition against bacteria and fungi. The leaf and root extracts of S. oblonga are prepared using low polar to high polar solvents in the Soxhlet apparatus and tested on the selected bacterial and fungal strains. Agar well diffusion and broth dilution methods evaluate antibacterial activity, antifungal activity, and Minimum Inhibitory Concentration (MIC) of extracts. Among the extracts tested, the ethyl acetate extract of root showed more antimicrobial activity against the tested bacterial and fungal strains. The most susceptible bacterial and fungal species against ethyl acetate extract are Micrococcus luteus, Mycobacterium tuberculosis, Microsporum canis, Trichophyton interdigitale, and Microsporum gypseum. The MIC for bacteria ranged from 13.0 to > 200 µg/ml, whereas for fungi, the MIC ranged from 25.9 to > 200 µg/ml. Ethyl acetate extract of root with 100 µg/ml concentration showed 29.1 mm and 28.7 mm zone of inhibition against bacterial strains M. luteus and M. tuberculosis, respectively. The ethyl acetate extract of root with a 100 µg/ml concentration showed 15.8, 15.2, and 15.6 mm zone of inhibition against fungal isolates M. canis, T. interdigitale, and M. gypseum, respectively. The activity of root and leaf extracts increased in a concentration-dependent manner, and further, the compounds isolated from the crude extracts of leaf and root showed antimicrobial activity. Structural elucidation of isolated compounds Lambertic acid and Ferruginol was done using NMR spectroscopy. Reports indicate that Lambertic acid was isolated previously, but the isolation of hydroxy Ferruginol from S. oblonga leaf extract was reported unprecedented.

Salacia pallescens Oliv. (Celastraceae) Scavenges Free Radicals and Inhibits Pro-inflammatory Mediators in Lipopolysaccharide-activated RAW Cells 264.7 Macrophages

OBJECTIVES

Salacia pallescens has folkloric anti-inflammatory claims, with little scientific investigation. Hence, the antioxidant and anti-inflammatory effects along with phytochemical components of the plant were investigated.

MATERIALS AND METHODS

The antioxidant property of S. pallescens leaf (SPL) methanol extract was evaluated using 1,1-diphenyl-2-picrylhydrazyl and nitric oxide inhibition assays. The anti-inflammatory property of SPL in lipopolysaccharide-stimulated RAW 264.7 macrophages was determined. The cytotoxicity of SPL was assessed in brine shrimp lethality assay (BSL) and against RAW 264.7 cells in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide based assay. Gas chromatography-mass spectrometry was employed to identify SPL phytochemical compounds.

RESULTS

SPL significantly scavenged free radical generated in the antioxidant assays and inhibited nitrite production in stimulated RAW 264.7 cells. Similarly, there was a 9-fold reduction in interleukin-6 produced in RAW 264.7 cells when exposed to the highest concentration of SPL. In addition, 50% lethal concentration of SPL was 455.58±82.35 µg/mL while cyclophosphamide gave 16.3±0.15 µg/mL in BSL test. Moreover, cell viability was not affected by SPL. Sixteen compounds were identified from SPL where thymol (29.79%), 3-carene (15.97%), and p-cymene (12.19%) are the most abundant.

CONCLUSION

Methanol extract of SPL showed antioxidant and anti-inflammatory activities by free radicals and cytokines inhibition. The activity observed may be related to the polyphenolic compounds in the plant.

In vitro and in vivo anti-leukemia activity of the stem bark of Salacia impressifolia (Miers) A. C. Smith (Celastraceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Salacia impressifolia (Miers) A. C. Smith (family Celastraceae) is a traditional medicinal plant found in the Amazon Rainforest known as "miraruíra", "cipó-miraruíra" or "panu" and is traditionally used to treat dengue, flu, inflammation, pain, diabetes, male impotency, renal affections, rheumatism and cancer.

AIM OF THE STUDY

The aim of this study was to investigate in vitro and in vivo anti-leukemia activity of the stem bark of S. impressifolia in experimental models.

MATERIALS AND METHODS

The in vitro cytotoxic activity of extracts, fractions and quinonemethide triterpenes (22-hydroxytingenone, tingenone and pristimerin) from the stem bark of S. impressifolia in cultured cancer cells was determined. The in vivo antitumor activity of the ethyl acetate extract (EAE) and of its fraction (FEAE.3) from the stem bark of S. impressifolia was assessed in C.B-17 severe combined immunodeficient (SCID) mice engrafted with human promyelocytic leukemia HL-60 cells.

RESULTS

The extract EAE, its fraction FEAE.3, and quinonemethide triterpenes exhibited potent cytotoxicity against cancer cell lines, including in vitro anti-leukemia activity against HL-60 and K-562 cells. Moreover, extract EAE and its fraction FEAE.3 inhibited the in vivo development of HL-60 cells engrafted in C.B-17 SCID mice. Tumor mass inhibition rates were measured as 40.4% and 81.5% for the extract EAE (20 mg/kg) and for its fraction FEAE.3 (20 mg/kg), respectively.

CONCLUSIONS

Ethyl acetate extract and its fraction from the stem bark of S. impressifolia exhibit in vitro and in vivo anti-leukemia activity that can be attributed to their quinonemethide triterpenes. These data confirm the ethnopharmacological use of this species and may contribute to the development of a novel anticancer herbal medicine.