Monozygotic twins discordant for schizophrenia differ in maturation and synaptic transmission.

Schizophrenia affects approximately 1% of the world population. Genetics, epigenetics, and environmental factors are known to play a role in this psychiatric disorder. While there is a high concordance in monozygotic twins, about half of twin pairs are discordant for schizophrenia. To address the question of how and when concordance in monozygotic twins occur, we have obtained fibroblasts from two pairs of schizophrenia discordant twins (one sibling with schizophrenia while the second one is unaffected by schizophrenia) and three pairs of healthy twins (both of the siblings are healthy). We have prepared iPSC models for these 3 groups of patients with schizophrenia, unaffected co-twins, and the healthy twins. When the study started the co-twins were considered healthy and unaffected but both the co-twins were later diagnosed with a depressive disorder. The reprogrammed iPSCs were differentiated into hippocampal neurons to measure the neurophysiological abnormalities in the patients. We found that the neurons derived from the schizophrenia patients were less arborized, were hypoexcitable with immature spike features, and exhibited a significant reduction in synaptic activity with dysregulation in synapse-related genes. Interestingly, the neurons derived from the co-twin siblings who did not have schizophrenia formed another distinct group that was different from the neurons in the group of the affected twin siblings but also different from the neurons in the group of the control twins. Importantly, their synaptic activity was not affected. Our measurements that were obtained from schizophrenia patients and their monozygotic twin and compared also to control healthy twins point to hippocampal synaptic deficits as a central mechanism in schizophrenia.

EphB2 activation in neural stem cells in the basolateral amygdala facilitates neurogenesis and enhances long-term memory.

Many brain diseases lead to a reduction in the number of functional neurons and it would be of value to be able to increase the number of neurons in the affected brain areas. In this study, we examined whether we can promote neural stem cells to produce mature neurons and whether an increase in the mature neurons can affect cognitive performance. We detected that the EphB2 receptor is localized in immature basolateral amygdala (BLA) neurons. We therefore aimed to increase the level of EphB2 activity in neural stem cells (NSCs) in the BLA and examine the effects on the production of mature neurons and cognition. Toward that end, we utilized a photoactivatable EphB2 construct (optoEphB2) to increase EphB2 forward signaling in NSCs in the BLA. We revealed that the activation of optoEphB2 in NSCs in the BLA increased the level of immature and mature neurons in the BLA. We further found that activation of optoEphB2 in BLA NSCs enhanced auditory, but not contextual, long-term fear memory formation. Impairing EphB2 forward signaling did not affect the level of immature and mature neurons in the BLA. This study provides evidence that NSCs can be promoted to produce mature neurons by activating EphB2 to enhance specific brain functions.

Synthesis of 6-alkoxy and 6-hydroxy-alkyl amine derivatives of braylin as vasorelaxing agents.

Braylin (10b) is a 8,8-dimethyl chromenocoumarin present in the plants of the family Rutaceae and Meliaceae and possesses vasorelaxing and anti-inflammatory activities. In this study, six 6-alkoxy (10b, 15-19), and twelve 6-hydroxy-alkyl amine (20a-20l) derivatives of braylin (11 and 12) were synthesized to delineate its structural requirement for vasorelaxing activity. The synthesized compounds were evaluated for vasorelaxation response in preconstricted intact rat Main Mesenteric Artery (MMA). The compounds showed l-type VDCC channel blockade depended and endothelium-independent vasorelaxation within the range of Emax < 50.00-96.70 % at 30 µM. Amongst all, 6-alkoxy derivatives were more active than 6-hydroxy-alkyl amine derivatives. The structural refinements about braylin showed that deletion of its methoxy group or homologation beyond ethoxy group presented deleterious effect on vasorelaxation response of braylin. Interestingly, substituting the ethoxy group in 10b presented the best activity and selectivity towards l-type VDCC channel blockade, a specific target cardiovascular function.

Synthesis and biological evaluation of substituted amide derivatives of C4-ageratochromene dimer analog.

Substituted amide derivatives of C4-ageratochromene dimer analog (19) were synthesized through structural modification of precocene-I (4a), isolated from the essential oil of Ageratum conyzoides L. The target compounds (18-20, 23I-VI, 24I-VI, and 25I-VI) were evaluated for their bone-forming effect using osteoblast differentiation assay. Seven compounds (23I, 23II, 23IV, 23VI, 24III, 24VI, and 25VI) presented good activity within 1 pM-1 nM concentration. At 1 pM concentration, the most active compound i.e. 23II showed effective mineralization of osteoblast cells along with expression of osteogenic marker genes viz RUNX 2, BMP-2, and type 1 collagen (Type-1 col) without any toxicity towards osteoblast cells. Single crystal X-ray analysis of 18 and 20 revealed that the core nucleus of these molecules bear phenyl rings in a Trans-stilbenoid system and had a good structural correlation with 17ß-estradiol (1) and diethylstilbestrol (DES, 3). In-silico study about 23II showed its structural complementarities with the LBD of estrogen receptor (ER) which indicated possible ER-mediated activity of compounds.

Synthesis and evaluation of substituted 8,8-dimethyl-8H-pyrano[2,3-f]chromen-2-one derivatives as vasorelaxing agents.

A series of substituted 8,8-dimethyl-8H-pyrano[2,3-f]chromen-2-ones (chromeno-coumarin hybrids) was synthesized from scopoletin (11) as vasorelaxing agents. The synthesized compounds 21a-f, 22, 23a-e and scopoletin (11) were evaluated for vasorelaxation in endothelium intact rat main mesenteric artery (MMA). Compounds 11, 21a, 21c-f and 22 showed significant vasorelaxation in precontracted MMA within the range of EC50 value 1.58-5.02 µM. These derivatives presented 29.40-70.89 fold increased sensitivity for experimental tissue compared to scopoletin (11), the parent molecule. Among others, 22 was found to be the most active compound which had EC50 1.58 µM with 70.89 fold increased sensitivity. The mechanistic evaluation of 22 showed that it exerted vasorelaxation through Ca2+-activated K+ (BKca) channel and the effect was endothelium-independent.

Essential oil from waste leaves of Curcuma longa L. alleviates skin inflammation.

BACKGROUND: Curcuma longa L. is an important industrial crop used by medicinal and cosmetic industries in the world. Its leaves are a waste material after harvesting rhizomes. The aim of the study was to evaluate the chemical and pharmacological profile of essential oil from waste leaves of Curcuma longa (EOCl) against skin inflammation. METHODS: EOCl was subjected to gas chromatography (GC) analysis for identification of essential oil constituents and its anti-inflammatory evaluation through in vitro and in vivo models. RESULTS: Chemical fingerprinting using GC and GC-MS analysis of EOCl revealed the presence of 11 compounds, representing 90.29% of the oil, in which terpinolene (52.88%) and α-phellandrene (21.13%) are the major components. In the in vitro testing EOCl inhibited the production of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß) in lipopolysaccharide (LPS) and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in the human keratinocyte cell line (HaCaT). Topical application of EOCl produced anti-inflammatory effects by reducing ear thickness, ear weight and ameliorating the level of pro-inflammatory cytokines (TNF-α, IL-6, IL-1ß) at protein and mRNA levels as well as regulating the overproduction of oxidative markers and restoring the histopathological damage in a TPA-induced mouse model of inflammation. CONCLUSION: These findings of topical anti-inflammatory properties of EOCl provide a scientific basis for medicinal use of this plant material against inflammatory disorders.

Synthesis of 3,5-dihydroxy-7,8-dimethoxy-2-(4-methoxyphenyl)benzopyran-4-one derivatives as anticancer agents.

Different alkyl amide (15a-l) and alkyl amine (16a-e) derivatives of 7,8-dimethoxy-3-hydroxy-2-(4-methoxyphenyl)benzopyran-4-one were synthesized and evaluated for their anticancer activity against five different cancer cell lines using SRB assay. Compounds 15e, 15i, 15j and 16a-e showed significant anticancer activity within the range of IC50 2.58-34.86µM. The most promising molecule, 16c, was further analyzed for its effect on cell cycle and apoptosis of estrogen receptor positive cancer cells (MCF-7 cells) which showed that 16c triggered apoptosis in MCF-7 cells and arrested cells population at sub-G0 (apoptotic) and G2M phase. In tubulin polymerization assay, 16c interfered with kinetics of tubulin polymerization.

EphrinB2 in excitatory neurons and astrocytes in the basolateral amygdala controls long-term fear memory formation.

EphrinB2 regulates synaptic transmission and morphology however its role in memory formation is unknown. Here we show that deleting ephrinB2 from excitatory neurons in the basolateral amygdala (BLA) of male mice impairs long-term (LTM), but not short-term (STM), fear memory formation. Deleting ephrinB2 from astrocytes in the BLA impairs fear LTM but not STM. Removing ephrinB2 from astrocytes in the BLA reduces the level of the excitatory amino acid transporter 1 (EAAT1) in these cells. Inhibiting EAAT1 activity in the BLA during fear conditioning, by its specific inhibitor UCPH-101, impairs fear LTM showing that EAAT1 in the BLA is needed for fear LTM formation. The administration of ephrinB2 into the BLA during fear conditioning training enhances fear LTM. Moreover, ephrinB2 increases the ability of fear conditioning to activate cells in the BLA as detected by c-Fos labeling. EphrinB2 therefore determines the threshold for fear memory formation. In contrast to mature neurons, we show that ephrinB2 in neural stem cells (NSCs) is not needed for fear LTM. Our study shows that ephrinB2 in the BLA determines the strength of long-term memory consolidation.

Feasibility of Achieving Dose Constraints for Dysphagia Aspiration-Related Structures and Its Clinical Significance in Intensity-Modulated Radiotherapy Planning of Head and Neck Cancer.

Introduction Dysphagia is commonly seen in patients with head and neck cancers after undergoing chemoradiotherapy and is often under-reported and also not given clinical importance. The quality of life of the patients can be significantly improved if the required dose constraints to the dysphagia aspiration-related structures (DARS) are achieved. The present study was conducted in order to determine the feasibility of achieving the dose constraints to DARS between the standard intensity-modulated radiotherapy (st-IMRT) arm and the dysphagia-optimized IMRT (do-IMRT) arm. Material and methods Sixty patients with head and neck cancer were recruited and randomized into two groups: In one group called the st-IMRT, constraints were not given to DARS, and in the other group called the do-IMRT, constraints were given to DARS. Treatment was given in the form of chemoradiation with a dose of 70 Gy in 35 fractions by IMRT technique, over seven weeks, 2 Gy per fraction along with weekly concurrent Cisplatin (35 mg/m2) in both the groups. Step and shoot IMRT setup was used for planning, and the system used for planning was Eclipse 13.6 (Varian Medical System, Inc., Palo Alto, CA, US); progressive resolution optimizer algorithm was used for optimization, and Anisotropic Analytical Algorithm algorithm was used for dose calculation. Truebeam was used for treatment delivery. DARS dosimetric parameters assessed were Dmean, V30, V50, V60, V70, D50, and D80. Radiation-induced toxicities to the skin, mucosa, larynx, salivary gland, and dysphagia and hematological toxicities were assessed in between both the groups during and after radiotherapy up to six months based on Common Terminology Criteria for Adverse Effects v5.0. p-values were calculated using the unpaired T-test. Results In the cohort of 60 patients with head and neck cancers, 95% were males. Dosimetric parameters of the planning target volume (PTV) were compared but were not found to be significant. In the dosimetry of the organs at risk, a p-value of some structures was found to be significant although the doses received were well within the tolerable limits in both arms. DARS dosimetry V60 and V70 of the inferior constrictor muscle was found to be statistically significant (p=0.01 and 0.008, respectively). V60 and V70 of larynx were also statistically significant (p=0.009 and 0.000, respectively). V70 and D50 of cricopharyngeus were found to be statistically significant (p=0.01 and 0.03, respectively), V30 and V60 for combined pharyngeal constrictor muscles were found to be statistically significant (p=0.02 and 0.01), and lastly, V60 for combined DARS was also significant (p=0.004). Post-treatment 33.3% of patients in the st-IMRT arm required Ryle's tube placement. No grade 4 toxicities were seen in either arm regarding hematological toxicities, acute or chronic radiation-induced toxicities. In site-wise comparison of doses, the p-value was not found to be significant in patients with oropharyngeal and oral cavity carcinomas but was found to be statistically significant in the larynx and hypopharynx subsites. Conclusion The feasibility of achieving dose constraints to the DARS was seen in cases of laryngeal and hypopharyngeal cancers where the constrictor muscles were at a distance from the PTV. Further, the feasibility of achieving dose constraints may be seen in lower-dose prescriptions either in postoperative cases or in low-risk clinical target volume nodal volumes.

Rac1 GTPase activation impairs fear conditioning-induced structural changes in basolateral amygdala neurons and long-term fear memory formation.

Long-term memory formation leads to enduring alterations in synaptic efficacy and neuronal responses that may be created by changes in neuronal morphology. We show that fear conditioning leads to a long-lasting increase in the volume of the primary and secondary dendritic branches, but not of distal branches, of neurons located at the basolateral amygdala (BLA). The length of the dendritic branches is not affected by fear conditioning. Fear conditioning leads to an enduring increase in the length and volume of dendritic spines, especially in the length of the spine neck and the volume of the spine head. Fear conditioning does not affect dendritic spine density. We further reveal that activation of Rac1 in BLA during fear conditioning impairs long-term auditory, but not contextual, fear conditioning memory. Activation of Rac1 during fear conditioning prevents the enduring increase in the dendritic primary branch volume and dendritic spines length and volume. Rac1 activation per se has no effect on neuronal morphology. These results show that fear conditioning induces changes known to reduce the inhibition of signal propagation along the dendrite and the increase in synaptic efficacy whereas preventing these changes, by Rac1 activation, impairs fear memory formation.

4-chloro eugenol interacts synergistically with artesunate against drug resistant P. falciparum inducing oxidative stress.

4-chloro eugenol (4CE), a semisynthetic analog of phytomolecule eugenol exhibited potent antiplasmodial activity with IC50 in the range of 1.5-5 µM against sensitive as well as drug resistant strain of P. falciparum. This analog also showed synergy with a clinically used antimalarial drug artesunate and was able to curtail the IC50 of artesunate up to 4-5 folds. Although, 4CE did not show any effect on heme polymerization, the most common drug target in the malaria parasite, it could increase the level of reactive oxygen species (ROS) and reactive nitrogen species (RNS) alone as well as in combination with artesunate. Further, 4CE induced oxidative stress was observed to affect the macromolecules in terms of DNA damage, protein carbonylation and lipid peroxidation. At the physiological level, cellular organelles like mitochondria and endoplasmic reticulum were observed to be get affected by 4CE in terms of membrane depolarization and calcium ion leakage respectively. These observations could be validated by expression analysis of oxidative stress responsive genes and proteins. Further, in in vivo assay, 4CE showed significant chemo-suppression of parasitemia as well as an increase in mean survival time in the murine malaria model. Interestingly, in combination with artesunate, 4CE showed higher chemo-suppression as well as enhanced mean survival time at a much lower concentrations of both the partners as compared to an individual dose of artesunate and 4CE. A combination of 4CE and artesunate was also observed to attenuate cerebral malaria pathogenesis.

Synthesis of eugenol derivatives and its anti-inflammatory activity against skin inflammation.

Eugenol is a phytochemical present in aromatic plants has generated considerable interest in the pharmaceutical industries mainly in cosmetics. A series of eugenol esters (ST1-ST7) and chloro eugenol (ST8) have been synthesized. The structures of newly synthesized compounds were confirmed by 1H and 13C NMR and mass spectrometry. In an effort to evaluate the pharmacological activity of eugenol derivatives, we explored its anti-inflammatory potential against skin inflammation using in-vitro and in-vivo bioassay. Synthesized derivatives significantly inhibited the production of pro-inflammatory cytokines against LPS-induced inflammation in macrophages. Among all derivatives, ST8 [Chloroeugenol (6-chloro, 2-methoxy-4-(prop-2-en-1-yl)-phenol)] exhibited most potent anti-inflammatory activity without any cytotoxic effect. We have further evaluated the efficacy and safety in in-vivo condition. ST8 exhibited significant anti-inflammatory activity against TPA-induced skin inflammation without any skin irritation effect on experimental animals. These findings suggested that ST8 may be a useful therapeutic candidate for the treatment of skin inflammation.

Pharmacological and phytochemical evaluation of Ocimum sanctum root extracts for its antiinflammatory, analgesic and antipyretic activities.

BACKGROUND: Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) increases risk of having a range of gastrointestinal problems. Therefore, new anti-inflammatory, analgesic, antipyretic drugs having lesser side effects are being searched all overthe world as alternatives to NSAIDs. AIMS: To evaluate the anti-inflammatory, analgesic and antipyretic profile of Ocimum sanctum root extracts. MATERIALS AND METHODS: Anti-inflammatory profile of hexane (STH), chloroform (STC), ethyl acetate (STE), butanol (STB) and water (STW) extracts of OS was carried out by using carrageenan induced paw edema. STE a most active extract was further validated in dose dependent manner for anti-inflammatory, analgesic and antipyretic activity as well as oral toxicity profile in small laboratory animals. Identification of bioactives flux and chemical signature of most active fraction STE was developed by using the high-performance liquid chromatography fingerprinting. RESULTS: An ethyl acetate fraction (STE) exhibit most potent anti-inflammatory activity followed by STB, STW, STC and STH. Dose response study of STE showed anti-inflammatory, analgesic and anti-pyretic potential in dose-dependent manner without any toxic effect at dose 2000 mg/kg. Chemical fingerprint revealed the presence of flavanoids. CONCLUSIONS: The present research revealed that STE possess anti-inflammatory, analgesic and anti-pyretic properties. However, future research is advocated to evaluate the pharmacological properties of isolated bioactive compounds.