Comparative transcriptome and metabolite profiling reveal diverse pattern of CYP-TS gene expression during corosolic acid biosynthesis in Lagerstroemia speciosa (L.) Pers.

KEY MESSAGE: Extensive leaf transcriptome profiling and differential gene expression analysis of field grown and elicited shoot cultures of L. speciosa suggest that differential synthesis of CRA is mediated primarily by CYP and TS genes, showing functional diversity. Lagerstroemia speciosa L. is a tree species with medicinal and horticultural attributes. The pentacyclic triterpene, Corosolic acid (CRA) obtained from this species is widely used for the management of diabetes mellitus in traditional medicine. The high mercantile value of the compound and limited availability of innate resources entail exploration of alternative sources for CRA production. Metabolic pathway engineering for enhanced bioproduction of plant secondary metabolites is an attractive proposition for which, candidate genes in the pathway need to be identified and characterized. Therefore, in the present investigation, we focused on the identification of cytochrome P450 (CYP450) and oxidosqualene cyclases (OSC) genes and their differential expression during biosynthesis of CRA. The pattern of differential expression of these genes in the shoot cultures of L. speciosa, elicited with different epigenetic modifiers (azacytidine (AzaC), sodium butyrate (NaBu) and anacardic acid (AA)), was studied in comparison with field grown plant. Further, in vitro cultures with varying (low to high) concentrations of CRA were systematically assessed for the expression of CYP-TS and associated genes involved in CRA biosynthesis by transcriptome sequencing. The sequenced samples were de novo assembled into 180,290 transcripts of which, 92,983 transcripts were further annotated by UniProt. The results are collectively given in co-occurrence heat maps to identify the differentially expressed genes. The combined transcript and metabolite profiles along with RT-qPCR analysis resulted in the identification of CYP-TS genes with high sequence variation. Further, instances of concordant/discordant relation between CRA biosynthesis and CYP-TS gene expression were observed, indicating functional diversity in genes.

Genomic and transcriptomic studies on flavonoid biosynthesis in Lagerstroemia indica.

BACKGROUND: Lagerstroemia indica is a widely cultivated ornamental woody shrub/tree of the family Lythraceae that is used as a traditional medicinal plant in East Asia and Egypt. However, unlike other ornamental woody plants, its genome is not well-investigated, which hindered the discovery of the key genes that regulate important traits and the synthesis of bioactive compounds. RESULTS: In this study, the genomic sequences of L. indica were determined using several next-generation sequencing technologies. Altogether, 324.01 Mb sequences were assembled and 98.21% (318.21 Mb) of them were placed in 24 pseudo-chromosomes. The heterozygosity, repeated sequences, and GC residues occupied 1.65%, 29.17%, and 38.64% of the genome, respectively. In addition, 28,811 protein-coding gene models, 327 miRNAs, 552 tRNAs, 214 rRNAs, and 607 snRNAs were identified. The intra- and interspecies synteny and Ks analysis revealed that L. indica exhibits a hexaploidy. The co-expression profiles of the genes involved in the phenylpropanoid (PA) and flavonoid/anthocyanin (ABGs) pathways with the R2R3 MYB genes (137 members) showed that ten R2R3 MYB genes positively regulate flavonoid/anthocyanin biosynthesis. The colors of flowers with white, purple (PB), and deep purplish pink (DPB) petals were found to be determined by the levels of delphinidin-based (Dp) derivatives. However, the substrate specificities of LiDFR and LiOMT probably resulted in the different compositions of flavonoid/anthocyanin. In L. indica, two LiTTG1s (LiTTG1-1 and LiTTG1-2) were found to be the homologs of AtTTG1 (WD40). LiTTG1-1 was found to repress anthocyanin biosynthesis using the tobacco transient transfection assay. CONCLUSIONS: This study showed that the ancestor L. indica experienced genome triplication approximately 38.5 million years ago and that LiTTG1-1 represses anthocyanin biosynthesis. Furthermore, several genes such as LiDFR, LiOMTs, and R2R3 LiMYBs are related to anthocyanin biosynthesis. Further studies are required to clarify the mechanisms and alleles responsible for flower color development.

Lagerstroemia macrocarpa extract inhibits Th2-mediated STAT6 signaling pathway in human keratinocytes.

In this study, we examined physiological functions as a key material to develop cosmeceuticals using extracts of Lagerstroemia macrocarpa Wall. Ex Kurz (L. macrocarpa). Initially, the L. macrocarpa extract was treated by different concentration and antioxidant assay (DPPH and ABTS) were performed to measure free radical scavenging ability. In the cytotoxicity experiment, the extract was treated into human epidermal keratinocytes with different concentrations to measure cytotoxicity. We found that the extract induces differentiation markers such as keratin (KRT)1, KRT2, KRT9, KRT10 in keratinocytes. Furthermore, the extract significantly induces involucrin (IVL), loricrin (LOR), claudin1 (CLDN1), and filaggrin (FLG) expression, suggesting that it may enhance skin barrier functions. Especially, the extract restored FLG expression inhibited by interleukin (IL)-4/IL-13 in in vitro atopic dermatitis-like model. Therefore, we expect L. macrocarpa extract will be an effective material to develop the therapeutic and cosmeceutical of atopic dermatitis.

Identifying potent inhibitory phytocompounds from Lagerstroemia speciosa against SARS-Coronavirus-2: structure-based virtual screening.

The ongoing spillover of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) calls for expedited countermeasure through developing therapeutics from natural reservoirs and/or the use of less time-consuming drug discovery methodologies. This study aims to apply these approaches to identify potential blockers of the virus from the longstanding medicinal herb, Lagerstroemia speciosa, through comprehensive computational-based screening. Nineteen out of 22 L. speciosa phytochemicals were selected on the basis of their pharmacokinetic properties. SARS-CoV-2 Main protease (Mpro), RNA-directed RNA polymerase (RdRp), Envelope viroporin protein (Evp) and receptor-binding domain of Spike glycoprotein (S-RBD), as well as the human receptor Angiotensin-converting enzyme-2 (hACE2) were chosen as targets. The screening was performed by molecular docking, followed by 100-ns molecular dynamic simulations and free energy calculations. 24-Methylene cycloartanol acetate (24MCA) was found as the best inhibitor for both Evp and RdRp, and sitosterol acetate (SA) as the best hit for Mpro, S-RBD and hACE2. Dynamic simulations, binding mode analyses, free energy terms and share of key amino acids in protein-drug interactions confirmed the stable binding of these phytocompounds to the hotspot sites on the target proteins. With their possible multi-targeting capability, the introduced phytoligands might offer promising lead compounds for persistent fight with the rapidly evolving coronavirus. Therefore, experimental verification of their safety and efficacy is recommended.

Antibacterial, Antioxidant, Larvicidal and Anticancer Activities of Silver Nanoparticles Synthesized Using Extracts from Fruits of Lagerstroemia speciose and Flowers of Couroupita guianensis.

The present study aimed to analyze the in vitro antibacterial, antioxidant, larvicidal and cytotoxicity properties of green synthesized silver nanoparticles (Ag NPs) using aqueous extracts from fruits of Lagerstroemia speciosa and flowers of Couropita guinensis. Synthesized Ag NPs were characterized using UV-DRS, FTIR, XRD, DLS, and High-Resolution SEM and TEM analyses. Absorption wavelength was observed at 386 nm by UV-DRS analysis and energy band gap was calculated as 3.24 eV. FTIR analysis showed the existence of various functional groups in the aqueous extract and in the NPs. DLS analysis showed the stability and particle size of the synthesized Ag NPs. SEM analysis revealed that Ag NPs are in a face centered cubic symmetry and spherical shape with a size of 23.9 nm. TEM analysis showed particle size as 29.90 nm. Ag NPs showed antibacterial activity against both Gram-positive and Gram-negative bacteria. DPPH scavenging trait of Ag NPs was ranging from 20.0 ± 0.2% to 62.4 ± 0.3% and observed significant larvicidal activity (LC50 at 0.742 ppm and LC90 at 6.061 ppm) against Culex quinquefasciatus. In vitro cytotoxicity activity of Ag NPs was also tested against human breast cancer (MCF-7) and fibroblast cells (L-929) and found that cells viabilities are ranging (500 to 25 µg/mL) from 52.5 ± 0.4 to 94.0 ± 0.7% and 53.6 ± 0.5 to 90.1 ± 0.8%, respectively. The synthesized Ag NPs have the potential to be used in the various biomedical applications.

Lagerstroemia speciosa Ameliorated Blood Pressure in LNAME Induced Hypertension in Experimental Rats through NO/cGMP and Oxidative Stress Modulation.

Cardiovascular disease is the primary reason for chronic heart diseases and mortality worldwide. Hypertension (HTN) is the utmost dominant risk factor for the evolution of several diseases. Herbal medicines, traditional medicinal herbs, and their extracts are widely utilized to treat and monitor HTN. Herbal components have been shown to help relax arteries and lower oxidative stress. The current study assesses the probable role of herbal plant extract Lagerstroemia speciosa (LS) in the LNAME induced HTN in rats. LNAME (50 mg/100 mL) in drinkable water was given to rats for five weeks. There was a significant upsurge in LNAME-treated hypertensive rats' blood pressure (BP). On treatment with LS, it ameliorates blood pressure. Further, LS also improved body weight, reduced heart weight, and heart hypertrophy. The NO/cGMP concentration was lowered along with a substantial upsurge in the level of glutathione and a decline in MDA level. The LS extract also reduced the inflammatory cytokine markers in the systemic circulation. In conclusion, thus, the extract of LS treatment can efficiently alleviate the BP, oxidative stress markers, and inflammation and improve NO/cGMP concentration in LNAME induced HTN in rats.

Lagerstroemia indica extract regulates human hair dermal papilla cell growth and degeneration via modulation of ß-catenin, Stat6, and TGF-ß signaling pathway.

BACKGROUND: Lagerstroemia indica (L. indica) is reported to have diverse biological activities including anti-inflammatory, anti-cancer, neuro-regulatory, antidiabetic, and antioxidant activity. AIMS: The purpose of this study is to examine the potential of hair growth promotion and/or hair loss prevention by L. indica extract. PATIENTS/METHODS: The effects of L. indica on hair growth have been studied in human hair follicle dermal papillary (hHFDP) cells and follicular organ culture ex vivo by cell proliferation assay, PCR, western blot analysis, and reporter gene activity assay. Moreover, a clinical trial was conducted in healthy volunteers. RESULTS: Lagerstroemia indica significantly promoted the proliferation of hHFDP cells, which was associated with increased expression of TCF/LEF, VEGF, and Gli1 mRNA, and inhibition of STAT6 and Smad2 mRNA. Treatment with L. indica also increased the TCF/LEF reporter gene activity but downregulated the SBE- and STAT6-luciferase activities. The expression of total ß-catenin, CDK4, and CDK2 were elevated, while that of STAT6 and SMAD2/3 was suppressed upon treatment with L. indica. In human hair follicles organ culture, L. indica significantly inhibited hair follicular degeneration. The clinical trial showed a statistically significant rise in total hair count in test group (n = 24) after 24 weeks of applying the hair tonic enriched with L. indica (141.46 ± 21.27 number/cm2 , p < 0.05). CONCLUSION: We suggest that L. indica extract prevents hair loss as well as stimulate hair growth by regulating the Wnt-ß-catenin, JAK3-STAT6, and TGF-ß1-Smad signaling pathways, and may be further developed as a novel functional cosmetic for preventing hair loss.

The Alleviating Effect of Lagerstroemia indica Flower Extract on Stretch Marks through Regulation of Mast Cells.

Striae distensae (SD) or stretch marks are common linear scars of atrophic skin with disintegrating extracellular matrix (ECM) structures. Although fibroblasts contribute to the construction of ECM structure in SD, some studies have reported that mast cell degranulation causes the disruption of ECM in early SD lesions. Lagerstroemia indica flower (LIF) has traditionally been used in India as a diuretic. However, little is known about the effect and molecular action of Lagerstroemia indica flower extract (LIFE) on alleviating SD. This study evaluated the effects of LIFE on mast cell degranulation and the synthesis of ECM components in fibroblasts. LIFE inhibits the adhesion of rat basophilic leukemia (RBL) cells, RBL-2H3 on fibronectin (FN) and the expression of integrin, a receptor for FN, thereby reducing focal adhesion kinase (FAK) phosphorylation. In addition, LIFE attenuated the allergen-induced granules and cytokine interleukin 3 (IL-3) through the adhesion with FN. Moreover, the conditioned medium (CM) of activated mast cells decreases the synthesis of ECM components, and LIFE restores the abnormal expressions induced by activated mast cells. These results demonstrate that LIFE suppresses FN-induced mast cell activation and promotes the synthesis of ECM components in fibroblast, which indicates that LIFE may be a useful cosmetic agent for SD treatment.

Effect of Banaba (Lagerstroemia speciosa) on Metabolic Syndrome, Insulin Sensitivity, and Insulin Secretion.

To evaluate the effect of Banaba (Lagerstroemia speciosa) on metabolic syndrome (MetS), insulin sensitivity, and insulin secretion. A randomized, double-blind, placebo-controlled clinical trial was carried out in 24 patients with diagnosis of MetS according to the International Diabetes Federation criteria. Body weight, waist circumference, and blood pressure were evaluated. Fasting plasma glucose (FPG) and insulin concentrations were measured every 30 min during 2 h after a 75-g dextrose load. Lipid profile was determined before and after the pharmacological intervention. Twelve patients received Banaba (500 mg) twice a day, before breakfast and dinner for 12 weeks. The remaining 12 patients received placebo at the same dosage. Body mass index, area under the curve (AUC) of glucose and insulin, insulin sensitivity, total insulin secretion, and the first phase of insulin secretion were calculated. After Banaba administration, there were significant decreases in systolic blood pressure (SBP) (121.5 ± 12.9 vs. 116.3 ± 9.8 mmHg, P = .050), FPG (5.9 ± 0.4 vs. 5.7 ± 0.4 mmol/L, P = .034), triglycerides (TG) (2.3 ± 0.4 vs. 1.7 ± 0.5 mmol/L, P = .021), very low-density lipoprotein (VLDL) (0.5 ± 0.1 vs. 0.3 ± 0.1 mmol/L, P = .021), AUC of insulin (50,675 ± 14,309 vs. 37,983 ± 19,298 mmol/L, P = .017), and insulinogenic index (0.4 ± 0.2 vs. 0.3 ± 0.2, P = .047). Eight patients (67%) of the Banaba group showed remission of MetS. In the placebo group, there was a downward trend toward statistical significance in the Stumvoll index (910.3 ± 514.1 vs. 651.0 ± 405.2, P = .062). Banaba administration leads to remission of MetS and a significant decrease in SBP, FPG, TG, VLDL, AUC of insulin, and total insulin secretion. Clinical Trial Registration number: NCT02767869.

Lagerstroemia speciosa (L.) Pers., ethanolic leaves extract attenuates dapsone-induced liver inflammation in rats.

Drug-induced liver injury is a common cause of acute liver failure. Dapsone is increasingly used in combination with rifampicin for the treatment of leprosy and also for several dermatological disorders. Clinically, abnormal liver function and focal bile duct destruction were reported after dapsone therapy. Lagerstroemia speciosa Pers., commonly known as Banaba has been traditionally used to treat various ailments including diabetes and obesity due to its antioxidant and anti-inflammatory efficacies. This study investigated the hepatoprotective effect of ethanolic banaba leaves extract (EBLE) against dapsone-induced hepatotoxicity in rats. Dapsone (30 mg/kg, i.p.) was administered twice daily for 30 days. In separate groups, rats were post-treated orally with EBLE (250 and 500 mg/kg) and silymarin (100 mg/kg) once daily for 30 days after dapsone administration. The marker enzymes of hepatotoxicity, oxidative stress markers, inflammatory markers and histopathology of liver were done. HPTLC analysis confirmed the presence of 12.87 µg of corosolic acid per mg of EBLE. Dapsone administration-induced significant (p < 0.001) elevation of marker enzymes of hepatotoxicity in serum. This treatment also increased lipid peroxidation (p < 0.001) and pro-inflammatory markers (tumor necrosis factor-alpha, transforming growth factor-beta, and nuclear factor kappa-B) expressions (p < 0.001) and decreased antioxidants (p < 0.001) such superoxide dismutase, catalase and glutathione in the liver tissue. All these abnormalities were significantly (p < 0.001) mitigated after EBLE (500 mg/kg) and silymarin post-treatments. The results of this study suggest that silymarin and EBLE can be used for dapsone-induced hepatotoxicity.

Lagerstroemia ovalifolia Exerts Anti- Inflammatory Effects in Mice of LPSInduced ALI via Downregulating of MAPK and NF-κB Activation.

Lagerstroemia ovalifolia Teijsm. & Binn. (LO) (crape myrtle) has reportedly been used as traditional herbal medicine (THM) in Java, Indonesia. Our previous study revealed that the LO leaf extract (LOLE) exerted anti-inflammatory effects on lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Based on this finding, the current study aimed to evaluate the protective effects of LOLE in a mouse model of LPS-induced acute lung injury (ALI). The results showed that treatment with LPS enhanced the inflammatory cell influx into the lungs and increased the number of macrophages and the secretion of the inflammatory cytokines in the bronchoalveolar lavage fluid (BALF) of mice. However, these effects were notably abrogated with LOLE pretreatment. Furthermore, the increase of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and monocyte chemoattractant protein-1 (MCP-1) expression in the lung tissues of mice with ALI was also reversed by LOLE. In addition, LOLE significantly suppressed the LPS-induced activation of the MAPK/NF-κB signaling pathway and led to heme oxygenase-1 (HO-1) induction in the lungs. Additionally, in vitro experiments showed that LOLE enhanced the expression of HO-1 in RAW264.7 macrophages. The aforementioned findings collectively indicate that LOLE exerts an ameliorative effect on inflammatory response in the airway of ALI mice.

Molecular mechanism of DLBS3733, a bioactive fraction of Lagerstroemia speciosa (L.) Pers., on ameliorating hepatic lipid accumulation in HepG2 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Lagerstroemia speciosa (L.) Pers., commonly known as banaba and locally known as bungur, is widely used in Indonesia and other countries as a folk remedy for various chronic diseases such as diabetes mellitus and hypertension. L. speciosa (L.) Pers. has been used and evaluated on conditions associated to liver diseases by altering cholesterol absorption, lipid metabolism, as well as the related gene expressions. AIM OF THE STUDY: The aim of this study is to evaluate the effect of DLBS3733, a standardized bioactive fraction of Lagerstroemia speciosa (L.) Pers. leaves, on ameliorating hepatic steatosis induced by oleic acid, and elucidate its mechanism of action to ameliorate lipid accumulation in HepG2 cells. MATERIALS AND METHODS: Effects of DLBS3733 on expression of genes and proteins associated with lipid metabolism were evaluated in HepG2 cells in this study. Genes associated with lipid metabolism were evaluated using PCR, while the protein levels were revealed using western blot and ELISA. Cellular lipid accumulations and triglyceride (TG) synthesis were measured using ELISA, and antioxidant assay was conducted using DPPH assay. RESULTS: DLBS3733 significantly reduced lipid accumulation and TG synthesis by 51% and 32% (p < 0.01), respectively, through the significant increment of adiponectin expression by 58% (p < 0.01). Subsequently, adiponectin enhanced PPARα expression and AMPK phosphorylation which further regulate the downstream signaling pathway of lipogenesis and lipolysis. Moreover, 2.5 µg/mL DLBS3733 was found to significantly downregulate the expression of HMGCR, ACC and SREBP by 66%, 61% and 36%, respectively (p < 0.01), as well as significantly upregulate CPT-1 by 300% at the protein level (P < 0.05). DLBS3733 was also found to possess high antioxidant activity, where the highest concentration exhibited DPPH inhibition activity by up to 93% (P < 0.01). CONCLUSIONS: We propose that DLBS3733 may provide a prevention on hepatic steatosis through its activity as anti-lipogenesis, anti-cholesterologenesis and pro-lipolysis in HepG2 cells. This is the first report that revealed the molecular mechanism of L. speciosa (L.) Pers. as a potential treatment of hepatic steatosis-related diseases.

Evaluation of a Nutraceutical Product with Probiotics, Vitamin D, Plus Banaba Leaf Extracts (Lagerstroemia speciosa) in Glycemic Control.

BACKGROUND: Dysbiosis is related to changes in the composition and behaviour of intestinal microbiota, which may contribute to an age-related decline in metabolic and immune system functioning (immune-senescence). OBJECTIVE: The microbiota-targeted dietary and probiotic interventions have been shown to favorably affect the host health by an enhancement of antioxidant activity, improving immune homeostasis, suppression of chronic inflammation, regulation of metabolism and prevention of insulin resistance. RESULTS: In our study, the use of specific probiotics strains improved the serum concentration of glycemic markers, thereby promoting better overall health. CONCLUSION: Probiotics may help correct defects in the gut microbial environment improving metabolic parameters, such as blood sugar levels, glycosylated hemoglobin and a decrease in body weight.

Lagerstroemia speciosa (L.) Pers. triggers oxidative stress mediated apoptosis via intrinsic mitochondrial pathway in HepG2 cells.

Hepatocellular carcinoma is the second leading cause of cancer-related mortality worldwide. Lagerstroemia speciosa Pers. (Lythraceae) commonly known as Banaba has been used in different forms in traditional medicinal systems for treating various diseases which include diabetes and obesity. In this study, we investigated the cytotoxic potential of ethanolic Banaba leaf extract (EBLE) in HepG2 cells. The phytochemical analysis of EBLE was performed by HPTLC. HepG2 cells were treated with EBLE at 25, 50, 100, and 150 µg/mL concentrations, and cytotoxicity was evaluated by MTT assay. Oxidative stress was assessed by the evaluation of lipid peroxidation, superoxide dismutase, and reduced glutathione. Apoptosis-related morphology was investigated by acridine orange and ethidium bromide (AO/EB) dual staining. Mitochondrial membrane potential (ΔΨm) was evaluated by JC-1 staining. Apoptosis-related marker genes were evaluated by qPCR. HPTLC analysis confirmed the presence of corosolic acid (12.87 µg/mg), berberine (3.19 µg/mg), and gallic acid (2.94 µg/mg) in EBLE. EBLE treatments caused significant and concentration-dependent cytotoxicity and oxidative stress in HepG2 cells. Dual staining with AO/EB confirmed membrane distortion and nuclear chromatin condensation upon EBLE treatments. JC-I staining revealed the loss of ΔΨm. Furthermore, at a molecular level, EBLE treatments interfere with Bax/Bcl-2 homeostasis and induced the pro-apoptotic marker genes such as cytochrome c, Apaf-1, and caspases 9 and 3. EBLE treatments caused cytotoxicity in HepG2 cells, and this could be due to the induction of oxidative stress and apoptosis via the intrinsic or mitochondrial pathway.

Corosolic Acid Attenuates Hepatic Lipid Accumulation and Inflammatory Response via AMPK/SREBPs and NF-κB/MAPK Signaling Pathways.

Corosolic acid (CA) is the main active component of Lagetstroemia speciosa and has been known to serve as several different pharmacological effects, such as antidiabetic, anti-oxidant, and anticancer effects. In this study, effects of CA on the hepatic lipid accumulation were examined using HepG2 cells and tyloxapol (TY)-induced hyperlipidemia ICR mice. CA significantly inhibited hepatic lipid accumulation via inhibition of SREBPs, and its target genes FAS, SCD1, and HMGCR transcription in HepG2 cells. These effects were mediated through activation of AMPK, and these effects were all abolished in the presence of compound C (CC, an AMPK inhibitor). In addition, CA clearly alleviated serum ALT, AST, TG, TC, low-density lipoprotein cholesterol (LDL-C), and increased high-density lipoprotein cholesterol (HDL-C) levels, and obviously attenuated TY-induced liver steatosis and inflammation. Moreover, CA significantly upregulated AMPK, ACC, LKB1 phosphorylation, and significantly inhibited lipin1, SREBPs, TNF-α, F4/80, caspase-1 expression, NF-κB translocation, and MAPK activation in TY-induced hyperlipidemia mice. Our results suggest that CA is a potent antihyperlipidemia and antihepatic steatosis agent and the mechanism involved both lipogenesis and cholesterol synthesis and inflammation response inhibition via AMPK/SREBPs and NF-κB/MAPK signaling pathways.

The anti-diabetic effect of eight Lagerstroemia speciosa leaf extracts based on the contents of ellagitannins and ellagic acid derivatives.

Previously, we have reported the opposite effects of compounds isolated from Lagerstroemia speciosa leaves on a glucose transport (GLUT4) assay. Ellagitannins from L. speciosa activated GLUT4, while ellagic acid derivatives showed an inhibitory effect. As part of our continuing research on anti-diabetic nutritional supplements, we herein compared the anti-diabetic effects of several extracts (LE1-8) from leaves of L. speciosa using different manufacturing processes based on the contents of ellagitannins and ellagic acid derivatives. Their anti-diabetic effects were evaluated through glucose uptake and adipocyte differentiation in 3T3-L1 cells in vitro as well as alloxan induced diabetic mice in vivo. These extracts were given to mice by gavage at doses of 0.25, 1.0, and 4.0 g per kg body weight once a day for 21 consecutive days. Results showed that LE1 (1.0 g kg-1), LE3 (1.0 or 4.0 g kg-1), LE4 (1.0 or 4.0 g kg-1), LE5 (0.25 or 1.0 or 4.0 g kg-1) and LE7 (1.0 or 4.0 g kg-1) showed significant anti-diabetic effects in alloxan-induced diabetic mice as indicated by the decreased levels of fasting blood glucose, body weight, serum biomarkers, tissue weight and body fat, and increased final insulin levels. LE8 (1.0 g kg-1) showed a moderate anti-diabetic effect as illustrated by the reduced fasting blood glucose level while LE2 and LE6 showed slight effects in alloxan-induced diabetic mice. The potential correlation of the content of ellagitannins, ellagic acid derivatives, and corosolic acid with the anti-diabetic activity was discussed.

Ethanolic Extract of Lagerstroemia Speciosa (L.) Pers., Induces Apoptosis and Cell Cycle Arrest in HepG2 Cells.

Lagerstroemia speciosa (L.) Pers., (Lythraceae) also called Banaba is a native plant of southeast Asia and is widely used in traditional medicinal system. Herbal tea from banaba leaves are used to reduce weight and diabetes. We investigated the cytotoxic potentials of ethanolic banaba leaves extract (EBLE) against human hepatocellular carcinoma (HepG2) cell line. Lagerstroemia speciosa leaves were extracted and obtained from M/s. Quimico Herbal Extract Manufacturer, Bengaluru, India, and it contains 20% corosolic acid. Cells were treated with 50, 100, and 150 µg/ml of EBLE for 24 h, and cytotoxicity was evaluated by MTT assay. Apoptosis-related morphology was investigated by DAPI nuclear staining. Protein and gene expressions of p-Akt, FOXO1, p53, MDM2, p21, p27, CDK4, cyclin D1, and E1 were evaluated through Western blotting and qPCR. EBLE treatments caused significant, concentration-dependent cytotoxicity. DAPI staining and flow cytometry studies showed chromatin condensation, increased apoptotic cell population and cell cycle arrest at subG0/G1 phase upon EBLE treatments respectively. Furthermore, EBLE treatments significantly increased the expressions of p53, p21, p27, FOXO1, while p-Akt, MDM2, CDK4, cyclin D1, and E1 expressions were downregulated. These findings suggested that EBLE induces G1-phase of cell cycle arrest and apoptosis in HepG2 cells. EBLE may serve as a therapeutic agent against hepatocellular carcinoma.

Lagerstroemia speciosa (L.) Pers Leaf Extract Attenuates Lung Tumorigenesis via Alleviating Oxidative Stress, Inflammation and Apoptosis.

One of the major etiological factors that account for lung cancer is tobacco use. Benzo(a)pyrene [B(a)P], one of the main constituents of tobacco smoke, has a key role in lung carcinogenesis. The present study was conducted to investigate the cytotoxicity of an aqueous ethanolic extract of Lagerstroemia speciosa (L.) Pers leaves (LLE) on human lung adenocarcinoma cells (A549), as well as its in vivo antitumor effect on a lung tumorigenesis mice model. Our results revealed that LLE possesses cytotoxic activity against the A549 cell line. Mice orally administered B(a)P (50 mg/kg body weight) showed an increase in relative lung weight with subsequent decrease in final body weight. Serum levels of tumor marker enzymes AHH, ADA and LDH and the inflammatory mediator NF-κB increased, while total antioxidant capacity (TAC) decreased. In addition, we observed the increased activity of metalloproteinases (MMP-2 and MMP-12) and levels of the tumor angiogenesis marker VEFG and the lipid peroxidation marker MDA, as well as decreased levels of the non-enzymatic antioxidant GSH and enzymatic antioxidants CAT and GSH-Px in lung tissues. Moreover, B(a)P administration up-regulated the expression of the COX-2 gene, pro-inflammatory cytokines TNF-α and IL-6, and an anti-apoptotic gene Bcl-2, and at the same time down-regulated expression of pro-apoptotic genes BAX and caspase-3 and the p53 gene. Pre- and post-treatment with LLE (250 mg/kg body weight) attenuated all these abnormalities. Histopathological observations verified the protective effect of LLE. Overall, the present data positively confirm the potent antitumor effect of L. speciosa leaves against lung tumorigenesis.

Oxidosqualene cyclase and CYP716 enzymes contribute to triterpene structural diversity in the medicinal tree banaba.

Pentacyclic triterpenes (PCTs) represent a major class of bioactive metabolites in banaba (Lagerstroemia speciosa) leaves; however, biosynthetic enzymes and their involvement in the temporal accumulation of PCTs remain to be studied. We use an integrated approach involving transcriptomics, metabolomics and gene function analysis to identify oxidosqualene cyclases (OSCs) and cytochrome P450 monooxygenases (P450s) that catalyzed sequential cyclization and oxidative reactions towards PCT scaffold diversification. Four monofunctional OSCs (LsOSC1,3-5) converted the triterpene precursor 2,3-oxidosqualene to either lupeol, ß-amyrin or cycloartenol, and a multifunctional LsOSC2 formed α-amyrin as a major product along with ß-amyrin. Two CYP716 family P450s (CYP716A265, CYP716A266) catalyzed C-28 oxidation of α-amyrin, ß-amyrin and lupeol to form ursolic acid, oleanolic acid and betulinic acid, respectively. However, CYP716C55 catalyzed C-2α hydroxylation of ursolic acid and oleanolic acid to produce corosolic acid and maslinic acid, respectively. Besides, combined transcript and metabolite analysis suggested major roles for the LsOSC2, CYP716A265 and CYP716C55 in determining leaf ursane and oleanane profiles. Combinatorial expression of OSCs and CYP716s in Saccharomyces cerevisiae and Nicotiana benthamiana led to PCT pathway reconstruction, signifying the utility of banaba enzymes for bioactive PCT production in alternate plant/microbial hosts that are more easily tractable than the tree species.

Investigation of biological activities of the flowers of Lagerstroemia speciosa, the Jarul flower of Bangladesh.

BACKGROUND: Lagerstroemia speciosa (L.) Pers. (Family: Lythraceae) is used in traditional medicine in the treatment of diarrhea, diabetes and other diseases. The study was performed to conduct antioxidant, cytotoxic, thrombolytic, membrane stabilizing, antimicrobial, peripheral and central analgesic and hypoglycemic activity assays and phenobarbitone sodium-induced sleeping time test using crude methanol extract of flowers of L. speciosa and its different partitionates. METHOD: The antioxidant potential was evaluated by determining the ability of the samples to scavenge 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical. The cytotoxic potential was examined following the procedures of brine shrimp lethality bioassay. Thrombolytic potential was assayed using streptokinase as standard. The samples were subjected to membrane stabilizing activity assay under heat induced condition. Antimicrobial potential was observed by disc diffusion method. The ability of the extract to inhibit writhing induced by acetic acid was determined in peripheral analgesic activity assay. The extract was also tested for central analgesic and hypoglycemic activities by tail flicking and tail tipping methods in Swiss albino mice model, respectively. CNS depressant activity was evaluated by an assay in which sleep was induced in mice using phenobarbitone sodium. RESULTS: The chloroform soluble fraction of L. speciosa extract demonstrated the highest antioxidant activity (IC50 = 4.20 ± 0.41 µg/ml) while the most prominent cytotoxic potency was showed by hexane soluble fraction (LC50 = 2.00 ± 0.31 µg/ml). Among the test samples, the carbon tetrachloride soluble fraction induced clot lysis (64.80 ± 0.27%) and prevented heat induced haemolysis (41.90 ± 0.10%) to the maximum extent. The largest zone of inhibition (19.0 mm) against Staphylococcus aureus, was also observed for the same fraction. In peripheral analgesic activity assay, 16.68% inhibition of writhing was documented for the L. speciosa extract (400 mg/kg body weight dose). The extract (400 mg/kg dose) also reduced blood sugar level by 56.12% after three hours of administration of glucose solution. In CNS depressant activity assay, mice of the sample group slept for shorter period of time compared to control group. CONCLUSIONS: From our investigation, it can be suggested that, the extract should be further studied for possible phytochemicals responsible for the observed biological activities.