Rubrofusarin

Cassiae Semen improves non-alcoholic fatty liver disease through autophagy-related pathway.[Pubmed:37538867]

Chin Herb Med. 2023 Mar 22;15(3):421-429.

OBJECTIVE: Cassiae Semen (CS, Juemingzi in Chinese) has been used for thousands of years in ancient Chinese history for relieving constipation, improving liver function as well as preventing myopia. Here we aimed to elucidate the anti-steatosis effect and underlying mechanism of CS against non-alcoholic fatty liver disease (NAFLD). METHODS: High-performance liquid chromatography (HPLC) was used to identify the major components of CS water extract. Mice were fed with a high-fat and sugar-water (HFSW) diet to induce hepatic steatosis and then treated with CS. The anti-NAFLD effect was determined by measuring serum biomarkers and histopathology staining. Additionally, the effects of CS on cell viability and lipid metabolism in oleic acid and palmitic acid (OAPA)-treated HepG2 cells were measured. The expression of essential genes and proteins involved in lipid metabolism and autophagy signalings were measured to uncover the underlying mechanism. RESULTS: Five compounds, including aurantio-obtusin, Rubrofusarin gentiobioside, cassiaside C, emodin and rhein were simultaneously identified in CS extract. CS not only improved the diet-induced hepatic steatosis in vivo, as indicated by decreased number and size of lipid droplets, hepatic and serum triglycerides (TG) levels, but also markedly attenuated the OAPA-induced lipid accumulation in hepatocytes. These lipid-lowering effects induced by CS were largely dependent on the inhibition of fatty acid synthase (FASN) and the activation of autophagy-related signaling, including AMP-activated protein kinase (AMPK), light chain 3-II (LC3-II)/ LC3-1 and autophagy-related gene5 (ATG5). CONCLUSION: Our study suggested that CS effectively protected liver steatosis via decreasing FASN-related fatty acid synthesis and activating AMPK-mediated autophagy, which might become a promising therapeutic strategy for relieving NAFLD.

Theoretical modelling of structure, vibrational and UV-vis absorbance spectra of rubrofusarin molecule.[Pubmed:36801731]

Spectrochim Acta A Mol Biomol Spectrosc. 2023 May 15;293:122469.

The structure of the Rubrofusarin molecule (CAS: 3567-00-8, IUPAC name 5,6-dihydroxy-8-methoxy-2-methyl-4H-benzo[g]chromen-4-one, molecular formula C(15)H(12)O(5)) and its possible rotational conformers and tautomer were investigated within DFT approach. It was noted that for a stable molecules the group symmetry is close to Cs. The smallest potential barrier for rotational conformers is associated with the methoxy group rotation. The rotation of hydroxyl groups leads to a stable states that are substantially higher in energy than the ground state. Modeling and interpretation of vibrational spectra for the case of the ground state molecule in the gas phase and methanol solution was carried out, the influence of the solvent is discussed. The modelling of electronic singlet transition within the TD-DFT approach and the interpretation of obtained UV-vis absorbance spectra were carried out. A relatively small shift in the two most active absorption bands wavelength takes place for methoxy group rotation conformer. At the same time the redshift of the HOMO-LUMO transition takes place for this conformer. Much larger long wavelength shift of the absorption bands was noted for the tautomer.

Anti-Inflammatory, Antiallergic and COVID-19 Main Protease (M(pro)) Inhibitory Activities of Butenolides from a Marine-Derived Fungus Aspergillus costaricaensis.[Pubmed:35599958]

ChemistrySelect. 2022 Mar 29;7(12):e202200130.

Amid the current COVID-19 pandemic, the emergence of several variants in a relatively high mutation rate (twice per month) strengthened the importance of finding out a chemical entity that can be potential for developing an effective medicine. In this study, we explored ethyl acetate (EtOAc) extract of a marine-derived fungus Aspergillus cosatricaensis afforded three butenolide derivatives, butyrolactones I, VI and V (1-3), two naphtho-gamma-pyrones, TMC-256 A1 (4) and Rubrofusarin B (5) and methyl p-hydroxyphenyl acetate (6). Structure identification was unambiguously determined based on exhaustive spectral analyses including 1D/2D NMR and mass spectrometry. The isolated compounds (1-6) were assessed for their in vitro anti-inflammatory, antiallergic, elastase inhibitory activities and in silico SARS-CoV-2 main protease (M(pro)). Results exhibited that only butenolides (1 and 2) revealed potent activities similar to or more than reference drugs unlike butyrolactone V (3) suggesting them as plausible chemical entities for developing lead molecules.

Phenolic Compounds From the Stems and Leaves of Berchemia lineata (L.) DC.[Pubmed:35494635]

Front Chem. 2022 Apr 14;10:889441.

Eight new phenolic compounds, named bercheminols A-H (1-8), and eleven known analogues were isolated from the stems and leaves of Berchemia lineata (L.) DC. Their structures including the absolute configurations were elucidated by extensive spectroscopic analysis, chemical method, and quantum chemical calculations. Compound 1 possesses an unprecedented 3,4-dihydro-11H-benzo[b]pyrano[4,3-e] oxepin-11-one skeleton. The other new compounds belong to three structural types of natural products, including naphthopyrones (2-5), flavonoids (6-7), and bibenzyl (8). The alpha-glucosidase inhibitory activities of the isolated compounds were assayed. As a result, vittarin-B (9), Rubrofusarin-6-O-beta-D-glucopyranoside (11), quercetin (14), kaempferol (15), and dihydrokaempferol (17) showed moderate inhibitory activities against alpha-glucosidase with IC(50) values of 22.5, 28.0, 36.5, 32.7, and 31.9 muM, respectively.

Role of extracellular signal-regulated kinase in rubrofusarin-enhanced cognitive functions and neurite outgrowth.[Pubmed:35093759]

Biomed Pharmacother. 2022 Mar;147:112663.

Memory-enhancing agents have long been required for various reasons such as for obtaining a good score in a test in the young and for retaining memory in the aged. Although many studies have found that several natural products may be good candidates for memory enhancement, there is still a need for better agents. The present study investigated whether Rubrofusarin, an active ingredient in Cassiae semen, enhances learning and memory in normal mice. Passive avoidance and Morris water maze tests were performed to determine the memory-enhancing ability of Rubrofusarin. To investigate synaptic function, hippocampal long-term potentiation (LTP) was measured. Western blotting was performed to determine protein levels. To investigate neurite outgrowth, DCX immunohistochemistry and cell culture were utilised. Rubrofusarin (1, 3, 10, 30 mg/kg) enhanced memory in passive avoidance and Morris water maze tests. Moreover, Rubrofusarin ameliorated scopolamine-induced memory impairment. In the Rubrofusarin-treated group, high-frequency stimulation induced higher LTP in the hippocampal Schaffer-collateral pathway compared to the control group. The Rubrofusarin-treated group showed a higher number of DCX-positive immature neurons with an increase in the length of dendrites compared to the control group in the hippocampal dentate gyrus region. In vitro experiments showed that Rubrofusarin facilitated neurite outgrowth in neuro2a cells through extracellular signal-regulated kinase (ERK). Finally, we found that extracellular signal-regulated kinase (ERK) is required for Rubrofusarin-induced enhancement of neurite outgrowth, learning and memory. These results demonstrate that Rubrofusarin enhances learning and memory and neurite outgrowth, and these might need activation of ERK pathway.

Hepatoprotective effects of Cassiae Semen on mice with non-alcoholic fatty liver disease based on gut microbiota.[Pubmed:34862475]

Commun Biol. 2021 Dec 3;4(1):1357.

Cassiae Semen (CS), the seeds of Cassia obtusifolia L. and C. tora L, have a long medicinal history in China, with suggestions for it to relieve constipation and exert hepatoprotective effects. However, the underlying mechanisms are still unclear. In this study, mice with high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) were used to study the hepatoprotective effects of CS. The relationship between gut microbiota and hepatoprotective effect mechanisms mediated by CS extracts, the total aglycone extracts of CS, Rubrofusarin-6-beta-gentiobioside, and aurantio-obtusin were examined. Our data indicate that CS extracts and components confer a protective effect by ameliorating lipid accumulation, intestinal barrier damage, liver damage, and inflammation on HFD-induced liver injury. Meanwhile, fecal microbe transplantation exerted the pharmacological effect of CS on HFD-fed mice; however, the efficacy of CS was inhibited or eliminated by antibiotic-induced dysbiosis. In conclusion, the therapeutic effects of CS on NAFLD were closely related to the gut microbiota, suggesting a role for TCM in treating disease.

Acetylcholine esterase inhibitory activity of green synthesized nanosilver by naphthopyrones isolated from marine-derived Aspergillus niger.[Pubmed:34506550]

PLoS One. 2021 Sep 10;16(9):e0257071.

Aspergillus niger metabolites exhibited a wide range of biological properties including antioxidant and neuro-protective effects and some physical properties as green synthesis of silver nanoparticles AgNP. The present study presents a novel evidence for the various biological activities of green synthesized AgNPs. For the first time, some isolated naphtho-gamma-pyrones from marine-derived Aspergillus niger, flavasperone (1), Rubrofusarin B (2), aurasperone A (3), fonsecinone A (4) in addition to one alkaloid aspernigrin A (7) were invistigated for their inhibitory activity of acetylcholine esterase AChE, a hallmark of Alzheimer's disease (AD). The ability to synthesize AgNPs by compounds 3, 4 and 7 has been also tested for the first time. Green synthesized AgNPs were well-dispersed, and their size was ranging from 8-30 nm in diameter, their morphology was obviously spherical capped with the organic compounds. Further biological evaluation of their AChE inhibitory activity was compared to the parent compounds. AgNps dramatically increased the inhibitory activity of Compounds 4, 3 and 7 by 84, 16 and 13 fold, respectively to be more potent than galanthamine as a positive control with IC50 value of 1.43 compared to 0.089, 0.311 and 1.53 of AgNPs of Compounds 4, 3 and 7, respectively. Also compound 2 showed moderate inhibitory activity. This is could be probably explained by closer fitting to the active sites or the synergistic effect of the stabilized AgNPs by the organic compouds. These results, in addition to other intrinsic chemical and biological properties of naphtho-gamma-pyrones, suggest that the latter could be further explored with a view towards other neuroprotective studies for alleviating AD.

Neuroprotective Effect of Aurantio-Obtusin, a Putative Vasopressin V(1A) Receptor Antagonist, on Transient Forebrain Ischemia Mice Model.[Pubmed:33805177]

Int J Mol Sci. 2021 Mar 24;22(7):3335.

Traditional Chinese medicines (TCMs) have been a rich source of novel drug discovery, and Cassia seed is one of the common TCMs with numerous biological effects. Based on the existing reports on neuroprotection by Cassia seed extract, the present study aims to search possible pharmacological targets behind the neuroprotective effects of the Cassia seeds by evaluating the functional effect of specific Cassia compounds on various G-protein-coupled receptors. Among the four test compounds (cassiaside, Rubrofusarin gentiobioside, aurantio-obtusin, and 2-hydroxyemodin 1-methylether), only aurantio-obtusin demonstrated a specific V(1A)R antagonist effect (71.80 +/- 6.0% inhibition at 100 microM) and yielded an IC(50) value of 67.70 +/- 2.41 muM. A molecular docking study predicted an additional interaction of the hydroxyl group at C6 and a methoxy group at C7 of aurantio-obtusin with the Ser341 residue as functional for the observed antagonist effect. In the transient brain ischemia/reperfusion injury C57BL/6 mice model, aurantio-obtusin attenuated the latency time that was reduced in the bilateral common carotid artery occlusion (BCCAO) groups. Likewise, compared to neuronal damage in the BCCAO groups, treatment with aurantio-obtusin (10 mg/kg, p.o.) significantly reduced the severity of damage in medial cornu ammonis 1 (mCA1), dorsal CA1, and cortex regions. Overall, the findings of this study highlight V(1A)R as a possible target of aurantio-obtusin for neuroprotection.

Screening of hypolipidemic active components in Jiang-Zhi-Ning and its preliminary mechanism research based on "active contribution value" study.[Pubmed:33596472]

J Ethnopharmacol. 2021 May 23;272:113926.

ETHNOPHARMACOLOGICAL RELEVANCE: Jiang-Zhi-Ning (JZN) is a traditional Chinese medicine formula, which has the effect of lowering blood lipid level and softening blood vessels. It is clinically used in the treatment of hyperlipidemia with significant curative effect. AIM OF THE STUDY: This study aims to screen the active components of JZN that are responsible for its blood lipids lowering effect and lay the foundation for elucidating pharmacodynamic material basis of the hypolipidemic effect of the formula. MATERIALS AND METHODS: The hyperlipidemia model was used to evaluate the efficacy of the JZN effective extraction with the TC and TG of rat plasma as evaluation index. Then the established ultra-high performance liquid chromatography coupled with electrospray ionization-quadrupole-time of flight-mass spectrometry (UPLC-ESI-Q-TOF-MS(n)) method was utilized to analyze the components of JZN effective extraction and the absorbed components in rat plasma, the potential active components were screened by using the combined analysis results of in vivo and in vitro component identification. Then an established ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-QqQ-MS(n)) method was used to determine the content of potential active components and its natural ratio in JZN effective extraction, and a potential active components combination (PACC) was formed accordingly. Then a HepG2 cell hyperlipidemia model induced by sodium oleate was used to study the hypolipidemic activity of PACC by detecting the content of TG level in the model. Meanwhile, the real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to conduct preliminary research on its hypolipidemic mechanism. Then combined with the concept of "combination index" in the "median-effect principle", to calculate the half inhibitory concentration (IC(50)) values of PACC and each monomer component on inhibiting the TG level in the cell model. Subsequently, the "activity contribution study" was carried out, and the components with the sum of the "activity contribution value" of 85% were finally selected as the hypolipidemic active components of JZN. RESULTS: The pharmacodynamics results showed that JZN effective extraction has displayed a good hypolipidemic effect. 45 components were identified in vitro, 108 components were identified from rat plasma, and 17 potential active components were screened out. The content determination result showed that the ratio of each potential active components in PACC as following: cassiaside C: Rubrofusarin-6-O-gentiobioside: aurantio-obtusin-6-O-glucoside: hyperoside: isoquercitrin: quercetin-3-O-glucuronide: (E)-2,3,5,4'-tetrahydroxystilbene-2-O-glucoside: rutin: emodin-8-O-glucoside: astragalin: armepavine: N-nornuciferine: coclaurine: O-nornuciferine: nuciferine: N-norarmepavine: higenamine = 3.30: 16.06: 9.15: 23.94: 98.40: 417.45: 189.68: 8.62: 1.28: 5: 3.51: 14.57: 1.06: 1.35: 1: 5.64: 6.06, and the activity study results showed that it has displayed a good hypolipidemic activity. Finally, the hypolipidemic active components screened out by the "activity contribution study" were: quercetin-3-O-glucuronide, (E)-2,3,5,4'-tetrahydroxystilbene-2-O-glucoside, isoquercitrin, O-nornuciferine, hyperoside and Rubrofusarin-6-O-gentiobioside. CONCLUSIONS: A scientific and rational approach of screening the hypolipidemic active ingredients of JZN has been developed in the current study. In addition, the research revealed the blood lipid lowering mechanism of those ingredients, which provide a solid basis for further elucidating the hypolipidemic pharmacodynamic material basis and action mechanism of JZN.

Secondary metabolites from a peanut-associated fungus Aspergillus niger IMBC-NMTP01 with cytotoxic, anti-inflammatory, and antimicrobial activities.[Pubmed:33375869]

Nat Prod Res. 2022 Mar;36(5):1215-1223.

Chemical investigation of a peanut-associated fungal strain Aspergillus niger IMBC-NMTP01 resulted in isolation and identification of 14 secondary metabolites, including two new, epi-aspergillusol (1) and aspernigin (3), and 12 known compounds: pyrophen (2), 2-(hydroxyimino)-3-(4-hydroxyphenyl)propanoic acid (4), aspergillusol A (5), Rubrofusarin B (6), nigerasperone A (7), fonsecin (8), TMC-256C1 (9), pyranonigrin A (10), orlandin (11), nigerasperone C (12), asperpyrone A (13), and 5-(hydroxymethyl)-2-furancarboxylic acid (14). Compounds 9, 12-14 showed cytotoxicity toward all six human cancer cell lines, including HepG2, KB, HL-60, MCF-7, SK-Mel2, and LNCaP, with IC(50) values ranging from 8.4 to 84.5 microM, compounds 3-5 were cytotoxic against five cancer cell lines except HepG2, whereas 1 exhibited cytotoxicity toward HepG2, KB, and MCF-7 cells. All of the compounds, except 2 and 13, inhibited NO overproduction in LPS-induced RAW264.7 cells. In addition, all of the compounds displayed antimicrobial effects against Enterococcus faecalis, whereas 13 compounds, except 10, significantly inhibited the growth of the yeast Candida albicans.

Aromatic Polyketides from a Symbiotic Strain Aspergillus fumigatus D and Characterization of Their Biosynthetic Gene D8.t287.[Pubmed:32575731]

Mar Drugs. 2020 Jun 20;18(6):324.

The chemical investigation of one symbiotic strain, Aspergillus fumigatus D, from the coastal plant Edgeworthia chrysantha Lindl led to the isolation of eight compounds (1-8), which were respectively identified as Rubrofusarin B (1), alternariol 9-O-methyl ether (2), fonsecinone D (3), asperpyrone A (4), asperpyrone D (5), fonsecinone B (6), fonsecinone A (7), and aurasperone A (8) by a combination of spectroscopic methods (1D NMR and ESI-MS) as well as by comparison with the literature data. An antimicrobial assay showed that these aromatic polyketides exhibited no remarkable inhibitory effect on Escherichia coli, Staphyloccocus aureus and Candida albicans. The genomic feature of strain D was analyzed, as well as its biosynthetic gene clusters, using antibiotics and Secondary Metabolite Analysis Shell 5.1.2 (antiSMASH). Plausible biosynthetic pathways for dimeric naphtho-gamma-pyrones 3-8 were first proposed in this work. A non-reducing polyketide synthase (PKS) gene D8.t287 responsible for the biosynthesis of these aromatic polyketides 1-8 was identified and characterized by target gene knockout experiment and UPLC-MS analysis.

Rubrofusarin Attenuates Chronic Restraint Stress-Induced Depressive Symptoms.[Pubmed:32414166]

Int J Mol Sci. 2020 May 13;21(10):3454.

The aim of this study was to examine whether Rubrofusarin, an active ingredient of the Cassia species, has an antidepressive effect in chronic restraint stress (CRS) mouse model. Although acute treatment using Rubrofusarin failed, chronic treatment using Rubrofusarin ameliorated CRS-induced depressive symptoms. Rubrofusarin treatment significantly reduced the number of Fluoro-Jade B-positive cells and caspase-3 activation within the hippocampus of CRS-treated mice. Moreover, Rubrofusarin treatment significantly increased the number of newborn neurons in the hippocampus of CRS-treated mice. CRS induced activation of glycogen synthase kinase-3beta and regulated development and DNA damage responses, and reductions in the extracellular-signal-regulated kinase pathway activity were also reversed by Rubrofusarin treatment. Microglial activation and inflammasome markers, including nod-like receptor family pyrin domain containing 3 and adaptor protein apoptosis-associated speck-like protein containing CARD, which were induced by CRS, were ameliorated by Rubrofusarin. Synaptic plasticity dysfunction within the hippocampus was also rescued by Rubrofusarin treatment. Within in vitro experiments, Rubrofusarin blocked corticosterone-induced long-term potentiation impairments. These were blocked by LY294002, which is an Akt inhibitor. Finally, we found that the antidepressant effects of Rubrofusarin were blocked by an intracerebroventricular injection of LY294002. These results suggest that Rubrofusarin ameliorated CRS-induced depressive symptoms through PI3K/Akt signaling.

Multiple Fungal Metabolites Including Mycotoxins in Naturally Infected and Fusarium-Inoculated Wheat Samples.[Pubmed:32316403]

Microorganisms. 2020 Apr 17;8(4):578.

In this study, the occurrence of multiple fungal metabolites including mycotoxins was determined in four different winter wheat varieties in a field experiment in Croatia. One group was naturally infected, while the second group was inoculated with a Fusarium graminearum and F. culmorum mixture to simulate a worst-case infection scenario. Data on the multiple fungal metabolites including mycotoxins were acquired with liquid chromatography with mass spectrometry (LC-MS/MS) multi-(myco)toxin method. In total, 36 different fungal metabolites were quantified in this study: the Fusarium mycotoxins deoxynivalenol (DON), DON-3-glucoside (D3G), 3-acetyldeoxynivalenol (3-ADON), culmorin (CULM), 15-hydroxyculmorin, 5-hydroxyculmorin, aurofusarin, Rubrofusarin, enniatin (Enn) A, Enn A1, Enn B, Enn B1, Enn B2, Enn B3, fumonisin B1, fumonisin B2, chrysogin, zearalenone (ZEN), moniliformin (MON), nivalenol (NIV), siccanol, equisetin, beauvericin (BEA), and antibiotic Y; the Alternaria mycotoxins alternariol, alternariolmethylether, altersetin, infectopyron, tentoxin, tenuazonic acid; the Aspergillus mycotoxin kojic acid; unspecific metabolites butenolid, brevianamid F, cyclo(L-Pro-L-Tyr), cyclo(L-Pro-L-Val), and tryptophol. The most abundant mycotoxins in the inoculated and naturally contaminated samples, respectively, were found to occur at the following average concentrations: DON (19,122/1504 microg/kg), CULM (6109/1010 microg/kg), 15-hydroxyculmorin (56,022/1301 microg/kg), 5-hydroxyculmorin (21,219/863 microg/kg), aurofusarin (43,496/1266 microg/kg). Compared to naturally-infected samples, Fusarium inoculations at the flowering stage increased the concentrations of all Fusarium mycotoxins, except enniatins and siccanol in Ficko, the Aspergillus metabolite kojic acid, the Alternaria mycotoxin altersetin, and unspecific metabolites brevianamid F, butenolid, cyclo(L-Pro-L-Tyr), and cyclo(L-Pro-L-Val). In contrast to these findings, because of possible antagonistic actions, Fusarium inoculation decreased the concentrations of the Alternaria toxins alternariol, alternariolmethylether, infectopyron, tentoxin, tenuazonic acid, as well as the concentration of the nonspecific metabolite tryptophol.

In Vitro and in Silico Human Monoamine Oxidase Inhibitory Potential of Anthraquinones, Naphthopyrones, and Naphthalenic Lactones from Cassia obtusifolia Linn Seeds.[Pubmed:31592482]

ACS Omega. 2019 Sep 18;4(14):16139-16152.

In recent years, Cassia seed extract has been reported as a neuroprotective agent in various models of neurodegeneration, mainly via an antioxidant mechanism. However, no one has previously reported the effects of Cassia seed extract and its phytochemicals on human monoamine oxidase (hMAO) enzyme activity. The seed methanol extract, the solvent-soluble fractions, and almost all isolated compounds displayed selective inhibition of hMAO-A isozyme activity. Interestingly, compounds obtusin (3), alaternin (8), aloe-emodin (9), questin (12), Rubrofusarin (13), cassiaside (15), toralactone 9-O-beta-gentiobioside (26), and (3S)-9,10-dihydroxy-7-methoxy-3-methyl-1-oxo-3,4-dihydro-1H-benzo[g]isochromene-3-carboxylic acid 9-O-beta-d-glucopyranoside (38) showed the most promising inhibition of the hMAO-A isozyme with IC(50) values of 0.17-11 muM. The kinetic study characterized their mode of inhibition and molecular docking simulation predicted interactions with Ile-335 and Tyr-326 in support of the substrate/inhibitor selectivity in respective isozymes. These results demonstrate that Cassia seed extract and its constituents inhibit hMAO-A enzyme activity with high selectivity and suggest that they could play a preventive role in neurodegenerative diseases, especially anxiety and depression.

Rubrofusarin as a Dual Protein Tyrosine Phosphate 1B and Human Monoamine Oxidase-A Inhibitor: An in Vitro and in Silico Study.[Pubmed:31460269]

ACS Omega. 2019 Jul 3;4(7):11621-11630.

A number of nature-derived biologically active compounds comprise glycosides. In some cases, the glycosidic residue is needed for bioactivity; however, in other cases, glycosylation just improves some pharmacokinetic/dynamic parameters. The patterns of protein tyrosine phosphatase 1B (PTP1B) and human monoamine oxidase A (hMAO-A) inhibition by Rubrofusarin 6-O-beta-d-glucopyranoside (1), Rubrofusarin 6-O-beta-d-gentiobioside (2), Rubrofusarin triglucoside (3), and cassiaside B2 (4) were compared with the aglycone, Rubrofusarin, isolated from Cassia obtusifolia seeds. Rubrofusarin showed potent inhibition against the PTP1B enzyme (IC(50); 16.95 +/- 0.49 muM), and its glycosides reduced activity (IC(50); 87.36 +/- 1.08 muM for 1 and >100 muM for 2-4) than did the reference drug, ursolic acid (IC(50); 2.29 +/- 0.04 muM). Similarly, in hMAO-A inhibition, Rubrofusarin displayed the most potent activity with an IC(50) value of 5.90 +/- 0.99 muM, which was twice better than the reference drug, deprenyl HCl (IC(50); 10.23 +/- 0.82 muM). An enzyme kinetic and molecular docking study revealed Rubrofusarin to be a mixed-competitive inhibitor of both these enzymes. In a western blot analysis, Rubrofusarin increased glucose uptake significantly and decreased the PTP1B expression in a dose-dependent manner in insulin-resistant HepG2 cells, increased the expression of phosphorylated protein kinase B (p-Akt) and phosphorylated insulin receptor substrate-1 (p-IRS1) (Tyr 895), and decreased the expression of glucose-6-phosphatase (G6Pase) and phosphoenol pyruvate carboxykinase (PEPCK), key enzymes of gluconeogenesis. Our overall results show that glycosylation retards activity; however, it reduces toxicity. Thus, Cassia seed as functional food and Rubrofusarin as a base can be used for the development of therapeutic agents against comorbid diabetes and depression.