Evaluation of therapeutic effect of Premna herbacea in diabetic rat and isoverbascoside against insulin resistance in L6 muscle cells through bioenergetics and stimulation of JNK and AKT/mTOR signaling cascade.

BACKGROUND: Premna herbacea Roxb., a perennial herb is well documented for its therapeutic uses among the traditional health care-givers of Assam, India. Scientific validation on the traditional use of the medicinal plant using modern technology may promote further research in health care. PURPOSE: This study evaluates the therapeutic potential of methanolic extract of P. herbacea (MEPH) against type 2 diabetes mellitus (T2DM) and its phytochemical(s) in ameliorating insulin resistance (IR), thereby endorsing the plant bioactives as effective anti-hyperglycemic agents. METHODS: The anti-diabetic potential of the plant extract was explored both in L6 muscle cells and high fructose high fat diet (HF-HFD) fed male Sprague Dawley (SD) rats. Bioactivity guided fractionation and isolation procedure yielded Verbascoside and Isoverbascoside (ISOVER) as bioactive and major phytochemicals in P. herbacea. The bioenergetics profile of bioactive ISOVER and its anti-hyperglycemic potential was validated in vitro by XFe24 analyzer, glucose uptake assay and intracellular ROS generation by flourometer, FACS and confocal microscopy. The potential of ISOVER was also checked by screening various protein markers via immunoblotting. RESULTS: MEPH enhanced glucose uptake in FFA-induced insulin resistant (IR) L6 muscle cells and decreased elevated blood glucose levels in HF-HFD fed rats. Isoverbascoside (ISOVER) was identified as most bioactive phytochemical for the first time from the plant in the Premna genus. ISOVER activated the protein kinase B/AMP-activated protein kinase signaling cascades and enhanced glucose uptake in IR-L6 muscle cells. ISOVER decreased the phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and c-Jun N-terminal kinase (JNK) and increased that of mammalian target of rapamycin (mTOR), thereby attenuating IR. However, molecular docking revealed that ISOVER increases insulin sensitivity by targeting the JNK1 kinase as a competitive inhibitor rather than mTOR. These findings were further supported by the bioenergetics profile of ISOVER. CONCLUSION: This study for the first time depicts the functional properties of ISOVER, derived from Premna herbacea, in ameliorating IR. The phytochemical significantly altered IR with enhanced glucose uptake and inhibition of ROS through JNK-AKT/mTOR signaling which may pave the way for further research in T2DM therapeutics.

3ß-Hydroxy-urs-12-en-28-oic Acid Modulates Dietary Restriction Mediated Longevity and Ameliorates Toxic Protein Aggregation in C. elegans.

Species from lower invertebrates to a spectrum of mammals show antiaging health benefits of phytochemical(s). Here, we explored the pro-longevity effects of a natural triterpenoid, ursolic acid (3ß-hydroxy-urs-12-en-28-oic acid; UA) in Caenorhabditis elegans with maximal life span being evident at 25 µM UA. Similar to eat-2 mutants, UA uptake by worm results in reduced fat storage and attenuation of reactive oxygen species (ROS), independent of superoxide dismutase(s) activation. The genetic requirements for UA-mediated longevity are quite similar to dietary restriction (DR) achieved through SKN-1/NRF-2 exhibiting upregulation of downstream target genes gcs-1 and daf-9. Longevity mechanism was independent of PHA-4/FOXA and attributed to partial dependence on sir-2.1. Altogether, our study suggests differential use of UA-elicited signaling cascades in nutrient sensing for longevity. Both the redox state and the proteostasis of an organism play critical role in aging and disease resistance. Interestingly, we observed a reduction of toxic protein aggregation in transgenic polyglutamine (polyQ) C. elegans model and UA-mediated JNK-1 (c-Jun-NH2-terminal kinase) activation in wild-type animals. Thus, our study demonstrates a small extent of prevention against proteotoxic stress by UA coupled with positive aspects of DR-mediated longevity.

3ß-Hydroxy-urs-12-en-28-oic acid confers protection against ZnONPs induced adversity in Caenorhabditis elegans.

Despite their well reported potent risk towards human health and environment Zinc oxide nanoparticles (ZnONPs) find an extensive commercial usage due to their antimicrobial properties. Here, we evaluated the efficacy of a natural triterpene ursolic acid (3ß-hydroxy-urs-12-en-28-oic acid; UA) for overcoming the cytotoxic challenges of ZnONPs employing Ceanorhabditis elegans. The 24h LC50 of Zn-ONPs (<50nm TEM) was deduced as 4.75mgL-1. UA (25µM) was observed to defend against this toxicity by attenuating Reactive Oxygen Species (ROS) resulting into better survival at 2mgL-1 in a time dependent behavior. However, reproductive health remains compromised. Our study identifies UA as a natural inducer of metallothionein proteins along with antioxidant potential. We demonstrate that UA induces upregulation of predominantly antioxidant genes, including the superoxide dismutases (sod-1, sod-5 and sod-3), glutathione S-transferase 7 (gst-7), heat shock protein (hsp-16.2) along with the metal exposure responsive metallothionein (mtl-1 and mtl-2). Moreover, UA also restores elevated transcript levels of gst-4 during ZnONPs stress conditions to normal by directly scavenging ROS owing to its own antioxidant potential. Altogether, the toxic aspects of NPs that can be avoided compensated or postponed by supplementation of phytochemical(s) in biological system underscore their potential implications in near future.

Sociodemographic Correlates of Unipolar and Bipolar Depression in North-East India: A Cross-sectional Study.

INTRODUCTION: Early diagnosis and management of depression is important for better therapeutic outcome. Strategies for distinguishing between unipolar and bipolar depression are yet to be defined, resulting improper management. This study aims at comparing the socio-demographic and other variables between patients with unipolar and bipolar depression, along with assessment of severity of depression. MATERIALS AND METHODS: This cross sectional study was conducted in a tertiary care psychiatry hospital in North-East India. The study included total of 330 subjects selected through purposive sampling technique from outpatient department after obtaining due informed consent. Mini-International Neuropsychiatric Interview (M.I.N.I.) version 6.0 and Beck Depression Inventory (BDI) were applied. Statistical Package for Social Sciences (SPSS) version 16.0 was applied for analysis. RESULTS: Bipolar group had onset of illness at significantly younger age with more chronicity (32.85 ± 11.084). Mean BDI score was significantly higher in the unipolar depressive group. CONCLUSION: Careful approach in eliciting symptom severity and associated socio demographic profiles in depressed patients may be helpful in early diagnosis of bipolar depression.

Exploitation of microbes for enhancing bacoside content and reduction of Meloidogyne incognita infestation in Bacopa monnieri L.

Despite the vast exploration of rhizospheric microbial wealth for crop yield enhancement, knowledge about the efficacy of microbial agents as biocontrol weapons against root-knot disease is scarce, especially in medicinal plants, viz., Bacopa monnieri. In the present investigation, rhizospheric microbes, viz., Bacillus megaterium, Glomus intraradices, Trichoderma harzianum ThU, and their combinations were evaluated for the management of Meloidogyne incognita (Kofoid and White) Chitwood and bacoside content enhancement in B. monnieri var CIM-Jagriti. A novel validated method Fourier transform near infrared was used for rapid estimation of total bacoside content. A significant reduction (2.75-fold) in root-knot indices was observed in the combined treatment of B. megaterium and T. harzianum ThU in comparison to untreated control plants. The same treatment also showed significant enhancement (1.40-fold) in total bacoside contents (plant active molecule) content using Fourier transform near-infrared (FT-NIR) method that analyses samples rapidly in an hour without solvent usage and provides ample scope for natural product studies.

Beta-caryophyllene modulates expression of stress response genes and mediates longevity in Caenorhabditis elegans.

Beta-caryophyllene (BCP) is a natural bicyclic sesquiterpene and is a FDA approved food additive, found as an active ingredient in essential oils of numerous edible plants. It possesses a wide range of biological activities including anti-oxidant, anti-inflammatory, anti-cancerous and local anesthetic actions. We used the well established Caenorhabditis elegans model system to elucidate the stress modulatory and lifespan prolonging action of BCP. The present study for the first time reports the lifespan extension and stress modulation potential of BCP in C. elegans. Upon evaluation, it was found that 50µM dose of BCP increased the lifespan of C. elegans by over 22% (P≤0.0001) and significantly reduced intracellular free radical levels, maintaining cellular redox homeostasis. Moreover, the results suggest that BCP modulates feeding behavior, pharyngeal pumping and body size effectively. Further, this compound also exhibited significant reduction in intestinal lipofuscin levels. In the present investigation, we have predicted possible biological molecular targets for BCP using molecular docking approaches and BCP was found to have interaction with SIR-2.1, SKN-1 and DAF-16. The prediction was further validated in vivo using mutants and transgenic strains unraveling underlying genetic mechanism. It was observed that BCP increased lifespan of mev-1 and daf-16 but failed to augment lifespan in eat-2, sir-2.1 and skn-1 mutants. Relative quantification of mRNA demonstrated that several genes regulating oxidative stress, xenobiotic detoxification and longevity were modulated by BCP treatment. The study unravels the involvement of multiple signaling pathways in BCP mediated lifespan extension.

Isolation, structure determination, and antiaging effects of 2,3-pentanediol from endophytic fungus of Curcuma amada and docking studies.

An endophytic fungus was isolated from the rhizomes of Curcuma amada (Zingiberaceae), which was identified as Fusarium oxysporum on the basis of its morphological and molecular characters. Chromatographic separation and spectroscopic analysis of the fungal metabolite (chloroform extract) led to the identification of one pure compound having molecular formula C5H12O2, i.e., 2,3-pentanediol (1). Activity analysis of compound 1 demonstrated improved antiaging (antioxidant, thermotolerance) properties against Caenorhabditis elegans, in comparison to a similar, commercially available molecule i.e., 1,5-pentanediol (2). The effective (lower) concentration of 1 significantly showed (28.6%) higher survival percentage of the worms under thermal stress (37 ºC) compared to its higher concentration (25.3%), while similar trends were followed in oxidative stress where (22.2%) higher survival percentage was recorded in comparison to untreated control. The compound 1, however, lacked potential antimicrobial activity, indicating the plausible ramification of the position of OH group in such bioactive molecules. In silico evaluation of these molecules against common as well as unique targets corroborated better antiaging potential of 1 in comparison to that of 2. The results for the first time indicated that the utilization of the endophytic fungi of C. amada could, thus, be a possible source for obtaining non-plant-based bioactive compounds having broader therapeutic applications pertaining to age-related progressions.

Genetic revelation of hexavalent chromium toxicity using Caenorhabditis elegans as a biosensor.

The interaction of heavy metals such as hexavalent chromium, Cr (VI) with the environment drastically influences living organisms leading to an ecological imbalance. Caenorhabditis elegans, a saprophytic nematode having 60-80% homology with human genes offers a distinct advantage to be used as a biosensor for the appraisal of heavy metal-induced environmental toxicity and risk monitoring. The present study examines the toxicity effects of K2Cr2O7 as Cr (VI) on stress-related gene expression and morphometric parameters of C. elegans under in vitro conditions to identify genetic markers for environmental pollution. Alterations in growth and modified gene expression were observed in Cr (VI)-exposed N2 worms. The 24-h median lethal concentration for Cr (VI) was observed as 158.5 mgl(-1). Use of the responses of stress-related gene expression suggests that C. elegans can be used as an efficient biosensor for figuring out the precise route of Cr (VI)-induced environmental toxicity in a quick, simple, and inexpensive manner.

Longevity-promoting effects of 4-hydroxy-E-globularinin in Caenorhabditis elegans.

In modern times, there has been a major increase in the use of plants or herbal constituents for the prevention of age-related disorders. 4-Hydroxy-E-globularinin (4-HEG) is an iridoid and a major component of Premna integrifolia. This investigation represents a breakthrough in geriatrics by showing the longevity-promoting activity of 4-HEG in the animal model Caenorhabditis elegans. 4-HEG (20µM) enhanced the mean life span of worms by over 18.8% under normal culture conditions and also enhanced their survival under oxidative stress. The longevity-promoting activity was associated with reduced reactive oxygen species (ROS) levels and fat accumulation in the worms. Gene-specific mutant studies verified the role of ROS detoxification pathways and simultaneous nuclear translocation of DAF-16 in the 4-HEG-mediated effects. Quantitative real-time PCR estimations and observations of transcriptional reporters indicated that 4-HEG was able to upregulate stress-inducible genes, viz., hsp-16.2 and sod-3. Thus, 4-HEG may serve as a lead compound of plant origin for the development of important nutraceuticals superseding the aging process.