Therapeutic Potential of Dillenia indica L. in Attenuating Hyperglycemia-Induced Oxidative Stress and Apoptosis in Alloxan-Administered Diabetic Mice.

BACKGROUND: Hyperglycemia-induced oxidative stress accelerates the process of apoptosis in tissues. Dilleniaindica (DI) is a medicinal plant, and its fruit contains many therapeutic properties. The therapeutic activity of the Methanolic Fruit Extract (MFE) of DI in attenuating oxidative stress and apoptosis in the liver and kidney tissues of alloxan-induced diabetic mice was analyzed in the present study. METHODS: High-Performance Thin Layer Chromatography (HPTLC) profiling of MFE was conducted. GLUT4 protein expression analysis and lipid peroxidation assays were conducted to check for MFE effect by administering in diabetic mice. An ultrastructural study was conducted for both the tissues. In apoptotic studies, the TUNEL assay and apoptotic protein expression analysis was conducted. RESULTS: High-Performance Thin Layer Chromatography (HPTLC) profiling of MFE showed the presence of two crucial antioxidants, ascorbic acid, and naringenin. In GLUT-4 protein expression analysis, MFE suppresses hyperglycemia by upregulating GLUT4 protein expression. Lipid peroxidation assay showed a decrease in malondialdehyde (MDA) upon MFE administration in diabetic mice. An ultrastructural study was conducted, and MFE was found to restore cellular alterations in diabetic tissues. In apoptotic studies, the TUNEL assay shows that MFE treatment showed fewer apoptotic cells than the diabetic group. The study also observed decreased caspase 3 protein expression and increased Bcl-2 protein expression. CONCLUSIONS: Therefore, it is inferred from the study that MFE can exert a protective effect by suppressing hyperglycemia and modulating oxidative stress and apoptosis in alloxan-administered diabetic mice.

Leaf Extract and Active Fractions of Dillenia pentagyna Roxb. Reduce In Vitro Human Cancer Cell Migration Via NF-κB Pathway.

BACKGROUND: Different parts of Dillenia pentagyna have long been used in traditional medicines to cure several diseases including cancer. However, the mechanism(s) of anti-cancer effects are still unknown. We aimed to elucidate the anti-metastatic potential of ethanolic extracts of leaves of D. pentagyna (EELDP) and active fractions of it in highly metastatic human cancer cells. METHODS: We screened different HPLC fractions of EELDP based on their anti-metastatic effect. We used TLC and ESI-MS for determining the presence of various phytochemicals in EELDP and fractions. We monitored in vitro anti-metastasis effect of EELDP (0-0.6 mg/ml) and active fractions (0-0.050 mg/ml) on various human cancer cells like A549, HeLa, and U2OS. RESULTS: EELDP significantly reduced cell viability and cell migration in A549, HeLa, and U2OS cells. However, higher sensitivity was observed in A549 cells. We screened 2 active HPLC fractions F6 and F8 having anti-MMPs activity. EELDP and active fractions reduced metastasis via the NF-κB pathway, decreased the expression of Vimentin, N-cadherin, and increased the expression of Claudin-1. CONCLUSION: Significant reduction of metastasis by EELDP at a dose of 0.1 mg/ml or by active fractions at 0.050 mg/ml implicates that the active compound(s) present in crude or fractions are extremely potent to control highly metastatic cancer.

Pretreatment of hydroethanolic extract of Dillenia indica L. attenuates oleic acid induced NAFLD in HepG2 cells via modulating SIRT-1/p-LKB-1/AMPK, HMGCR & PPAR-α signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Dillenia indica L. is an edible plant from the Dilleniaceae family present in the forest of India and other Asian countries. Different parts of this plant are being used in the traditional system of medicines for various diseases like diabetes, indigestion, asthma, jaundice, and rheumatic pain by various rural communities. This plant is very common among Khamptis traditional healers, the rural community of the Dhemaji district of Assam, ethnic communities of Dibru-Saikhowa Biosphere Reserve of Northeast, India for various medicinal uses. It is observed as a 'vat' suppressant and 'pitta' boosting medicine in Ayurveda. AIM OF THE STUDY: The aim of this research was to evaluate the effect of hydroethanolic extract of Dillenia indica leaf (DI-HET) against non-alcoholic fatty liver disease (NAFLD) as it is reported effective against jaundice in traditional medicine. We are also planning to see the various molecular mechanisms responsible for its effect if it is efficacious. STUDY DESIGN/METHOD: An in vitro model for NAFLD was employed in this study. For this HepG2 cells were incubated with 100 µM of oleic acid (OA) for 24 h. For evaluation of the effect of DI-HET, the extracts (5 or 10 µg/mL) were pretreated to the OA group. Fenofibrate was the positive control. Various parameters relevant to lipogenesis and ß-oxidation of fatty acids like intracellular lipid accumulation, reactive oxygen species (ROS), mitochondrial stress, and key proteins were studied. RESULTS: DI-HET significantly reduced the intracellular lipid accumulation in OA treated cells. And also substantially decreased the expression of lipogenic proteins and increased ß-oxidation in the OA group. OA induced ROS generation was found to reduce with DI-HET treatment. Western blot analysis showed that the expression of LXR-α, SREBP-1C, SREBP-2, HMGCR, FAS, CD-36, and ACOX-1 were downregulated while that of SIRT-1, p-LKB-, p-AMPK, p-ACC, CPT-1, and PPAR-α upregulated in DI-HET treatment. LCMS/MS analysis showed the presence of polyphenols like naringenin, catechin, epicatechin, shikimic acid, syringic acid, vanillic acid, and kaempferol. CONCLUSION: These results suggest that DI-HET is effective against NAFLD by activation of the SIRT-1/p-LKB-1/AMPK signaling pathway via polyphenols present in the extract.

Root positioning and trait shifts in Hibbertia racemosa as dependent on its neighbour's nutrient-acquisition strategy.

Nutrient-poor ecosystems globally exhibit high plant diversity. One mechanism enabling the co-existence of species in such ecosystems is facilitation among plants with contrasting nutrient-acquisition strategies. The ecophysiological processes underlying these interactions remain poorly understood. We hypothesized that root positioning plays a role between sympatric species in nutrient-poor vegetation. We investigated how the growth traits of the focal mycorrhizal non-cluster-rooted Hibbertia racemosa change when grown in proximity of non-mycorrhizal Banksia attenuata, which produces cluster roots that increase nutrient availability, compared with growth with conspecifics. Focal plants were placed in the centre of rhizoboxes, and biomass allocation, root system architecture, specific root length (SRL), and leaf nutrient concentration were assessed. When grown with B. attenuata, focal plants decreased root investment, increased root growth towards B. attenuata, and positioned their roots near B. attenuata cluster roots. SRL was greater, and the degree of localized root investment correlated positively with B. attenuata cluster-root biomass. Total nutrient contents in the focal individuals were greater when grown with B. attenuata. Focal plants directed their root growth towards the putatively facilitating neighbour's cluster roots, modifying root traits and investment. Preferential root positioning and root morphological traits play important roles in positive plant-plant interactions.

Secondary metabolites from Tetracera potatoria stem bark with anti-mycobacterial activity.

ETHNOPHARMACOLOGICAL RELEVANCE: Tetracera potatoria Afzel. Exg. Don (Dilleniaceae) is a medicinal plant used traditionally in Africa for the treatment of tuberculosis related ailments and respiratory infections. The antibacterial activity of the medium polar extracts of T. potatoria leaves and stem bark was recently reported against Mycobacterium smegmatis (MIC 25µg/mL) and M. aurum (65µg/mL), two fast-growing Mycobacterium strains used as model micro-organisms for the more pathogenic strain Mycobacterium tuberculosis (Fomogne-Fodjo et al., 2014). The aim of this study was consequently to isolate the compounds possibly contributing to this activity, and which may therefore be promising precursors to be used for the development of novel anti-TB drugs. MATERIALS AND METHODS: T. potatoria medium polar extract [MeOH/DCM (1:1, v/v)] was fractionated sequentially with petroleum ether to which EtOAC and MeOH were gradually added to increase the polarity. The examination of T. potatoria extract and its fractions was guided by bioassays for anti-mycobacterial activity against M. smegmatis (ATCC 23246) and M. aurum (NCTC 10437) using the minimum inhibitory concentration (MIC) method. All the isolated compounds were structurally elucidated using spectroscopic techniques and evaluated for their anti-mycobacterial activity. RESULTS: Two novel secondary metabolites (1, 2) named tetraceranoate and N-hydroxy imidate-tetracerane, together with five known compounds [ß-stigmasterol (3), stigmast-5-en-3ß-yl acetate (4), betulinic acid (5), betulin (6) and lupeol (7)] were isolated and identified. Tetraceranoate exhibited the best activity against M. smegmatis with a minimum inhibitory concentration (MIC) of 7.8µg/mL, while ß-stigmasterol, betulinic acid and betulin showed appreciable anti-mycobacterial activity against both strains (MIC 15µg/mL). CONCLUSION: Seven compounds were isolated from the medium polar extract [MeOH/DCM (1:1, v/v)] of T. potatoria stem bark. Only tetraceranoate one of the isolated compounds showed antibacterial activity against M. smegmatis having efficacy as high as rifampicin (one of a three drug regimen recommended in the initial phase short-course anti-tuberculosis therapy). Thus, tetraceranoate might be an interesting target for systematic testing of anti-TB treatment and management. This research supports the use of T. potatoria in African traditional medicine for the treatment of tuberculosis related symptoms.

Antioxidant and Hypolipidemic Activity of the Hydroethanolic Extract of Curatella americana L. Leaves.

High levels of reactive oxygen species in the body and hyperlipidemia are key factors for the development of cardiovascular diseases such as atherosclerosis. The present study investigated the antioxidant and hypolipidemic activity of hydroethanolic extract of Curatella americana L. leaves (ExC). The antioxidant activity of ExC was assessed by 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH) scavenging capacity and protection against hemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH), followed by quantification of malondialdehyde (MDA). Wistar rats with hyperlipidemia induced by high-fructose diet (60%) were treated for 60 days with water, simvastatin (30 mg·Kg(-1)), ciprofibrate (2 mg·Kg(-1)), and ExC (200 mg·Kg(-1)). ExC revealed IC50 of 6.0 ± 0.5 µg·mL(-1), an intermediary value among positive controls used in the assay of DPPH scavenging capacity. At all concentrations (50 to 125 µg·mL(-1)) and times (60 to 240 min) evaluated, ExC protected erythrocytes against AAPH-induced hemolysis, which was confirmed by lower MDA levels. In vivo tests showed a reduction of 34 and 45%, respectively, in serum concentration of cholesterol and triglycerides in hyperlipidemic rats treated with ExC, a similar effect compared to the reference drugs, simvastatin and ciprofibrate, respectively. Together, the results showed the antioxidant activity of ExC and its ability to improve the serum lipid profile in hyperlipidemic rats.

Induction of Apoptosis in MCF-7 Cells via Oxidative Stress Generation, Mitochondria-Dependent and Caspase-Independent Pathway by Ethyl Acetate Extract of Dillenia suffruticosa and Its Chemical Profile.

Dillenia suffruticosa, which is locally known as Simpoh air, has been traditionally used to treat cancerous growth. The ethyl acetate extract of D. suffruticosa (EADs) has been shown to induce apoptosis in MCF-7 breast cancer cells in our previous study. The present study aimed to elucidate the molecular mechanisms involved in EADs-induced apoptosis and to identify the major compounds in the extract. EADs was found to promote oxidative stress in MCF-7 cells that led to cell death because the pre-treatment with antioxidants α-tocopherol and ascorbic acid significantly reduced the cytotoxicity of the extract (P<0.05). DCFH-DA assay revealed that treatment with EADs attenuated the generation of intracellular ROS. Apoptosis induced by EADs was not inhibited by the use of caspase-inhibitor Z-VAD-FMK, suggesting that the cell death is caspase-independent. The use of JC-1 dye reflected that EADs caused disruption in the mitochondrial membrane potential. The related molecular pathways involved in EADs-induced apoptosis were determined by GeXP multiplex system and Western blot analysis. EADs is postulated to induce cell cycle arrest that is p53- and p21-dependent based on the upregulated expression of p53 and p21 (P<0.05). The expression of Bax was upregulated with downregulation of Bcl-2 following treatment with EADs. The elevated Bax/Bcl-2 ratio and the depolarization of mitochondrial membrane potential suggest that EADs-induced apoptosis is mitochondria-dependent. The expression of oxidative stress-related AKT, p-AKT, ERK, and p-ERK was downregulated with upregulation of JNK and p-JNK. The data indicate that induction of oxidative-stress related apoptosis by EADs was mediated by inhibition of AKT and ERK, and activation of JNK. The isolation of compounds in EADs was carried out using column chromatography and elucidated using the nuclear resonance magnetic analysis producing a total of six compounds including 3-epimaslinic acid, kaempferol, kaempferide, protocatechuic acid, gallic acid and ß-sitosterol-3-O-ß-D-glucopyranoside. The cytotoxicity of the isolated compounds was determined using MTT assay. Gallic acid was found to be most cytotoxic against MCF-7 cell line compared to others, with IC50 of 36 ± 1.7 µg/mL (P<0.05). In summary, EADs generated oxidative stress, induced cell cycle arrest and apoptosis in MCF-7 cells by regulating numerous genes and proteins that are involved in the apoptotic signal transduction pathway. Therefore, EADs has the potential to be developed as an anti-cancer agent against breast cancer.