Cancer cells adapt FAM134B/BiP mediated ER-phagy to survive hypoxic stress.

In the tumor microenvironment, cancer cells experience hypoxia resulting in the accumulation of misfolded/unfolded proteins largely in the endoplasmic reticulum (ER). Consequently, ER proteotoxicity elicits unfolded protein response (UPR) as an adaptive mechanism to resolve ER stress. In addition to canonical UPR, proteotoxicity also stimulates the selective, autophagy-dependent, removal of discrete ER domains loaded with misfolded proteins to further alleviate ER stress. These mechanisms can favor cancer cell growth, metastasis, and long-term survival. Our investigations reveal that during hypoxia-induced ER stress, the ER-phagy receptor FAM134B targets damaged portions of ER into autophagosomes to restore ER homeostasis in cancer cells. Loss of FAM134B in breast cancer cells results in increased ER stress and reduced cell proliferation. Mechanistically, upon sensing hypoxia-induced proteotoxic stress, the ER chaperone BiP forms a complex with FAM134B and promotes ER-phagy. To prove the translational implication of our mechanistic findings, we identified vitexin as a pharmacological agent that disrupts FAM134B-BiP complex, inhibits ER-phagy, and potently suppresses breast cancer progression in vivo.

Anti-proliferative potential of phytochemical fractions isolated from Simarouba glauca DC leaf.

Emerging advancements in anticancer drug discovery research are leaning towards the plant-based bioactive fractions, which is a cocktail of naturally abundant two or more substances with unique proportions, exhibiting greater potential to combat cancers than the individual molecules. Thus, isolation and characterization of anti-cancer activity enriched fractions from plants is gaining scientific attention. Consistent with this view, one of the evidence-based traditional medicinal plants, well known for its anti-cancer potential, Simarouba glauca (SG) leaf has been scientifically examined to identify and isolate the potent anti-cancer fraction. The dried SG leaves were extracted successively with the solvents of increasing polarity. The phytochemical characterization of obtained extracts and fractions were carried out to determine the phenolic acid composition. All fractions were individually examined for anti-cancer property in cancer cells representing lungs, cervix, breast, colon and rectum in vitro. Among all fractions tested, the chloroform (SGC) and ethyl acetate (SGEA) extracts showed potent anti-proliferative effects by triggering apoptosis. In summary, our findings demonstrate that the extracts SGC and SGEA have potent anti-cancer activities compared to other fractions of SG leaf and thus warrant further pre-clinical studies to establish scientific basis for the anticancer potentials of SG.

Desferrioxamine and dextromethorphan combination exhibited synergistic effect and reversed the catalepsy behaviour in 6-hydroxydopamine hydroydopamine administered rats through regulating brain glutamate levels.

OBJECTIVE: To investigate the effect of desferrioxamine (DFO) and dextromethorphan (DXM) combination in animal model of Parkinson's disease (PD). METHODS: The PD was induced in rats through intracerebroventricular administration of 6-hydroxydopamine (6-OHDA) using stereotaxic apparatus. The animals were subjected to behavioural assessments and neurobiochemicals estimation followed by immunohistochemistry staining of neuron specific enolase (NSE) in striatum. KEY FINDINGS: Desferrioxamine and DXM combination has significantly reversed the catalepsy behaviour and elevated the antioxidant enzymes (SOD, CAT, GSH) and dopamine levels. Interestingly, the level of glutamate, nitric oxide, cytokines (IL-1ß, TNF-α) and NSE expressions were found to be decreased in striatum region of 6-OHDA-administered rats. The combination of DFO and DXM has shown synergism in most of the parameters studied, when compared to per se treatment. CONCLUSIONS: The reversal of catalepsy behaviour represents the protective effect of above combination on dopamine neurons in striatum from 6-OHDA toxicity. The mechanism of DFO and DXM combination might be attributed through attenuation of glutamate-induced excitotoxicity in neurons through ameliorating the reactive oxygen species and pro-inflammatory cytokines release. Treatment with DFO and DXM combination could control the multiple events in the pathogenesis of PD.

Hypoxia Induced ER Stress Response as an Adaptive Mechanism in Cancer.

It is evident that regions within tumors are deprived of oxygen, which makes the microenvironment hypoxic. Cancer cells experiencing hypoxia undergo metabolic alterations and cytoprotective adaptive mechanisms to survive such stringent conditions. While such mechanisms provide potential therapeutic targets, the mechanisms by which hypoxia regulates adaptive responses-such as ER stress response, unfolded protein response (UPR), anti-oxidative responses, and autophagy-remain elusive. In this review, we summarize the complex interplay between hypoxia and the ER stress signaling pathways that are activated in the hypoxic microenvironment of the tumors.

Pluronic lecithin organogel of 5-aminosalicylic acid for wound healing.

5-Aminosalicylic acid (5-ASA) is an aminosalicylate anti-inflammatory drug, which is also known as mesalazine or mesalamine. Currently employed in treating inflammatory bowel disease, ulcerative colitis, inflamed anus or rectum, and maintain remission in Crohn's disease. Evidence from the researchers highlighted its significant re-epithelization in allergic asthma, aphthous, and gastric ulcerative conditions. The objective of the study was to formulate the pluronic lecithin organogel (PLO) containing 5-ASA and evaluate its wound-healing ability in a full thickness excision wound rat model. The data obtained from in silico docking studies revealed 5-ASA is having an affinity towards the transforming growth factor-beta (TGF-ß) specifically towards beta1. Among various formulations prepared (F1 to F8), F1, and F6 have shown a maximum in vitro drug release with optimum pH and viscosity. From MTT assay it was found that selected PLO formulations showed no toxicity and enhanced cell proliferation in HaCaT cell lines. In vivo wound-healing studies in albino Wistar rats has revealed that PLO accelerates wound closure and reepithelization to the statistically significant level on day 3 (p < .05) in comparison with untreated wounds. In conclusion, the overall results suggest that 5-ASA PLO gel is a potential therapeutic option for the treatments of wounds, however, further studies are highly warrened to determine the various mechanisms of 5-ASA in regulating the cell migration and reepithelization in wound healing to outspread its use in clinics.

Tricaproin Isolated From Simarouba glauca Inhibits the Growth of Human Colorectal Carcinoma Cell Lines by Targeting Class-1 Histone Deacetylases.

While anticancer properties of Simarouba glauca (SG, commonly known as Paradise tree) are well documented in ancient literature, the underlying mechanisms leading to cancer cell death begin to emerge very recently. The leaves of SG have been used as potential source of anticancer agents in traditional medicine. Recently attempts have been made to isolate anticancer agents from the leaves of SG using solvent extraction, which identified quassinoids as the molecules with tumoricidal activity. However, it is not known whether the anti-cancer potential of SG leaves is just because of quassinoids alone or any other phytochemicals also contribute for the potency of SG leaf extracts. Therefore, SG leaves were first extracted with hexane, chloroform, ethyl acetate, 70% ethanol, water and anti-cancer potential (for inhibiting colorectal cancer (CRC) cells HCT-116 and HCT-15 proliferation) determined using Sulforhodamine-B (SRB) assay. The chloroform fraction with maximal anticancer activity was further fractionated by activity-guided isolation procedure and structure of the most potent compound determined using spectral analysis. Analysis of the structural characterization data showed the presence of tricaproin (TCN). TCN inhibited CRC cells growth in a time- and dose dependent manner but not the normal cell line BEAS-2B. Mechanistically, TCN reduced oncogenic Class-I Histone deacetylases (HDACs) activity, followed by inducing apoptosis in cells. In conclusion, the anti-cancer potential of SG is in part due to the presence of TCN in the leaves.

Development and validation of simultaneous estimation method for curcumin and piperine by RP-UFLC.

Curcumin and piperine are proven for their potent medicinal benefits to treat various diseases and they are most commonly used combination in various Indian systems of medicine such as Ayurveda, Siddha and Unani. The objective of the present work is to develop a simultaneous estimation of curcumin and piperine by reverse phase Ultra-fast liquid chromatographic (RP-UFLC) method. The chromatographic separation was performed on a C8 column (250 x 4.6 mm, 5µ i.d.) stationary phase using a mobile phase of 25mM potassium dihydrogen ortho phosphate buffer (pH 3.5) and acetonitrile (30: 70 v/v) at a flow rate of lml/min at detection wave length of 280nm. The calibration curve was plotted in the concentration range of 0-2200ng/ml and found to be linear for both curcumin (r(2)=0.996) and piperine (r(2)=0.999). The method was validated for parameters such as accuracy, sensitivity, precision, linearity, specificity, ruggedness and robustness as per ICH guidelines. The developed simple, precise and specific method can be used as a quality control tool for qualitative and quantitative estimation of curcumin and piperine in various food products, herbal medicines and nutraceuticals.

Neuroprotective effect of Tinospora cordifolia ethanol extract on 6-hydroxy dopamine induced Parkinsonism.

OBJECTIVE: The present study investigates the neuroprotective activity of ethanol extract of Tinospora cordifolia aerial parts against 6-hydroxy dopamine (6-OHDA) lesion rat model of Parkinson's disease (PD). MATERIALS AND METHODS: T. cordifolia ethanol extract (TCEE) was standardized with high performance thin layer chromatography using berberine. Experimental PD was induced by intracerebral injection of 6-OHDA (8 µg). Animals were divided into five groups: sham operated, negative control, positive control (levodopa 6 mg/kg) and two experimental groups (n = 6/group). Experimental groups received 200 and 400 mg/kg of TCEE once daily for 30 days by oral gavage. Biochemical parameters including dopamine level, oxidative stress, complex I activity and brain iron asymmetry ratio and locomotor activity including skeletal muscle co-ordination and degree of catatonia were assessed. RESULTS: TCEE exhibited significant neuroprotection by increasing the dopamine levels (1.96 ± 0.20 and 2.45 ± 0.40 ng/mg of protein) and complex I activity (77.14 ± 0.89 and 78.50 ± 0.96 nmol/min/mg of protein) at 200 and 400 mg/kg respectively when compared with negative control group. Iron asymmetry ratio was also significantly attenuated by TCEE at 200 (1.57 ± 0.18) and 400 mg/kg (1.11 ± 0.15) when compared with negative control group. Neuroprotection by TCEE was further supported by reduced oxidative stress and restored locomotor activity in treatment groups. CONCLUSION: Results show that TCEE possess significant neuroprotection in 6-OHDA induced PD by protecting dopaminergic neurons and reducing the iron accumulation.

Effect of crude extract of Eugenia jambolana Lam. on human cytochrome P450 enzymes.

The fruit of Eugenia jambolana Lam. is very popular for its anti-diabetic property. Previous studies on the crude extract of E. jambolana (EJE) have successfully explored the scientific basis for some of its traditional medicinal uses. Considering its wide use and consumption as a seasonal fruit, the present study investigates the ability of E. jambolana to interact with cytochrome P450 enzymes. The standardized EJE was incubated with pooled human liver microsomes to assess the CYP2C9-, CYP2D6-, and CYP3A4-mediated metabolism of diclofenac, dextromethorphan, and testosterone, respectively. The metabolites formed after the enzymatic reactions were quantified by high performance liquid chromatography. EJE showed differential effect on cytochrome P450 activities with an order of inhibitory potential as CYP2C9 > CYP3A4 > CYP2D6 having IC50 of 76.69, 359.02, and 493.05 µg/mL, respectively. The selectivity of EJE for CYP2C9 rather than CYP3A4 and CYP2D6 led to perform the enzyme kinetics to explicate the mechanism underlying the inhibition of CYP2C9-mediated diclofenac 4'-hydroxylation. EJE was notably potent in inhibiting the reaction in a non-competitive manner with Ki of 84.85 ± 5.27 µg/mL. The results revealed the CYP2C9 inhibitory potential of EJE with lower Ki value suggesting that EJE should be examined for its potential pharmacokinetic and pharmacodynamic interactions when concomitantly administered with other drugs.

Antioxidant activity of Caesalpinia sappan heartwood.

Antioxidant activity of Caesalpinia sappan heartwood was studied both by in vitro and in vivo models. The ethyl acetate, methanol and water extracts exhibited strong antioxidant activity as evidenced by the low IC50 values in both 1,1-diphenyl-2-picryl hydrazyl (DPPH) and nitric oxide methods. The values were found to be less or comparable to those of ascorbic acid and rutin, the standards used. Administration of the successive methanol and water extracts at 50 and 100 mg/kg body weight given for four days prior to carbon tetrachloride (CCl4) treatment caused a significant increase in the level of superoxide dismutase (SOD) and catalase and a significant decrease in the level of thiobarbituric acid reactive substances (TBARS), when compared to CCl4 treated control in both liver and kidney. These changes observed at 100 mg/kg body weight treatment were comparable to those observed for standard vitamin E at 50 mg/kg treatment. The results support significant antioxidant nature of Caesalpinia sappan heartwood extracts.