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Well known as the center for learning and memory, hippocampus is the crucial brain region to study synaptic plasticity in the context of cellular fundamental mechanisms such as long‐term depression (LTD) and long‐term potentiation (LTP). However, despite years of extensive research, the key to our LTD queries and their induction mechanisms has not been fully understood. Previously, we reported the induction of late‐LTD (L‐LTD) in the distally located synapses of apical branch of hippocampal CA1 dendrites using strong low‐frequency stimulation (SLFS). In contrast synapses at the proximal site could not express L‐LTD. Thus, in the present study, we wanted to investigate whether or not synapses of apical dendritic branch at the proximal location could induce and maintain LTD and its related properties in in vitro rat hippocampal slices. Results indicated that the SLFS in the distal and proximal region triggered the plasticity related proteins (PRP) synthesis in both regions, as evident by the induction and maintenance of L‐LTD in the distal region by virtue of synaptic and cross‐tagging. In addition, the application of emetine at the time of proximal input stimulation prevented the transition of early‐LTD (E‐LTD) into L‐LTD at the distal region, proving PRP synthesis at the proximal site. Further, it was observed that weak low‐frequency stimulation (WLFS) could induce E‐LTD in the proximal region along with LTD‐specific tag‐setting at the synapses. In conclusion, the current study suggests unique findings that the synaptic and cross‐tagging mediate L‐LTD expression is maintained in the proximal location of hippocampus apical CA1 dendrites. [ABSTRACT FROM AUTHOR]

Tamoxifen is a selective oestrogen receptor modulator widely used in the treatment of breast cancer. Tamoxifen potentially affects mitochondrial functions as it acts as an uncoupling agent and a powerful inhibitor of mitochondrial electron transport chain. There is concern for the deleterious effects of tamoxifen. Taurine is known to have membrane stabilizing and antioxidant properties. We studied effect of taurine pre-treatment on the toxicity of tamoxifen in mouse liver mitochondria focusing specifically on the redox cycle biomarkers. Tamoxifen caused a significant rise in the mitochondrial lipid peroxidation, protein carbonyl content and superoxide radical generation. There was a significant change in the mitochondrial thiol profile in the tamoxifen-treated animals. Pre-treatment of mice with taurine (100 mg/kg) markedly lowered mitochondrial lipid peroxidation, protein carbonyl content and superoxide radical generation. It also restored decreased enzymatic and non-enzymatic antioxidants of mitochondria. It is suggested that taurine has a potential role in ameliorating tamoxifen-induced mitochondrial toxicity, and the protection is afforded either by reversing the decline of antioxidants or by the direct free radical-scavenging activity. [ABSTRACT FROM AUTHOR]

STIM1 and CRACM1 (or Orail) are essential molecular components mediating store-operated Ca2+ entry (SOCE) and Ca2+ release-activated Ca2+(CRAC) currents. Although STIM1 acts as a luminal Ca~+ sensor in the endoplasmic reticulum (ER), the function of STIM2 remains unclear. Here we reveal that STIM2 has two distinct modes of activating CRAC channels: a store-operated mode that is activated through depletion of ER Ca2+ stores by inositol 1,4,5-trisphosphate (InsP3) and store-independent activation that is mediated by cell dialysis during whole-cell perfusion. Both modes are regulated by calmodulin (CAM). The store-operated mode is transient in intact cells, possibly reflecting recruitment of CaM, whereas loss of CaM in perfused cells accounts for the persistence of the store-independent mode. The inhibition by CaM can be reversed by 2-aminoethoxydiphenyl borate (2-APB), resulting in rapid, store-independent activation of CRAC channels. The aminoglycoside antibiotic G418 is a highly specific and potent inhibitor of STIM2-dependent CRAC channel activation. The results reveal a novel bimodal control of CRAC channels by STIM2, the store dependence and CaM regulation, which indicates that the STIM2/CRACM1 complex may be under the control of both luminal and cytoplasmic Ca2+ levels. [ABSTRACT FROM AUTHOR]

Presents findings of a study explaining the role of dopamine agonists in slowing Parkinson's disease by the inhibition of the cascade leading to apoptotic cell death with mitochondrial permeability transition pore (PTP) as a potential target. Identity of the PTP by dose-dependent cyclosporin A blockade; Result of the application of the dopamine-D2 agonist pramipexole (PPX) to the PTP; Attenuation of PTP blockade by PPX using inorganic phosphate; Role of PPX in the swelling of mitochondria.

Problem: Spontaneous preterm birth (sPTB) is a global health issue. Studies suggest infection and infection‐based inflammatory responses are major risk factors for sPTB. Considering the important role of anti‐inflammatory proteins in pregnancy, the study aimed to find the association between anti‐inflammatory LGALS13 gene variants IVS2‐22 A/G (rs2233706) and IVS3+72 T/A (rs2233708) and the risk of sPTB during Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum infection in Indian population. Method of study: Placental samples of 160 sPTB and 160 term women were collected. Pathogens were detected by PCR. The genotyping of LGALS13 gene variants IVS2‐22 A/G (rs2233706) and IVS3+72 T/A (rs2233708) was done by qualitative real‐time PCR using allelic discrimination method (VIC‐ and FAM‐labeled). Results: The frequency of AG or GG genotype of LGALS13 IVS2‐22A/G polymorphism (rs2233706) was 75.5% in infected sPTB cases and 14.4% in uninfected sPTB cases and 7.3% in term birth controls (p <.0001), while the frequency of TA or AA genotype of LGALS13 IVS3+72T/A polymorphism (rs2233708) was 83.6% in infected sPTB cases and 18% in uninfected sPTB cases and 12.7% in term birth controls (p <.0001). The genotypic frequencies for both the variants of LGALS13 were statistically significant (p <.0001) in the infected sPTB versus uninfected sPTB and term birth controls. Conclusions: Study reveals strong association between the presence of immunological gene variants LGALS13 IVS2‐22 A/G (rs2233706) and LGALS13 IVS3+72 T/A (rs2233708) and risk of sPTB during C. trachomatis, M. hominis and U. urealyticum infection. [ABSTRACT FROM AUTHOR]

In continuation to our previous studies on cyanopyrimidine derivatives as anticancer agents, we further designed, synthesized, and evaluated new 3,4,5‐trimethoxy phenyl ring pendant sulfur‐containing cyanopyrimidine derivatives (4a–m) with a particular lipophilic behavior. In this work, we have varied the chain length from isopropyl to isopentyl and evaluated their anticancer activities. To study the antiproliferative spectrum, in vitro evaluation was piloted against a panel of 60 cancer cell lines at the National Cancer Institute, United States. Compound 4g (NSC: D‐813664) displayed the most promising broad‐spectrum anticancer activity with high growth inhibition of various cell lines representing action against multiple cancers diseases. It showed percentage growth inhibition of 84.01 and 76.94 against SR leukemia and HCT‐116 colon cancer cell lines. Absorption, distribution, metabolism, excretion, and toxicity studies and reverse screening were also performed to identify the potential targets of designed molecules. It was concluded that 6‐(3,4,5‐trimethoxyphenyl) pyrimidine‐5‐carbonitrile derivatives exhibited its anticancer activity through different targets and hence could be further structurally modified and optimized to develop more potent multi‐targeting anticancer agents. [ABSTRACT FROM AUTHOR]

Benzimidazole, the benzo derivative of imidazole, is a class of bicyclic aromatic organic compound consisting of six‐membered benzene ring fused to five‐membered imidazole at 4‐ and 5‐positions of the imidazole ring. It is a vital pharmacophore of many biologically active heterocyclic compounds with a variety of pharmacological activities. Over the time, benzimidazole and its derivatives have evolved as vibrant heterocyclic systems due to their potency in a wide range of bioactive compounds like analgesics, antifungals, anti‐inflammatory, antihypertensives, proton pump inhibitors, anti‐HIV, antiviral, and so on. Multi‐drug resistance in cancer that led to the failure of many chemotherapeutic drugs is a major concern. Various approaches are being developed to overcome this problem. One of them is target based drug discovery, which is an effective method to develop a novel anticancer drug. To develop newer drugs, previously reported work needs to be studied. Keeping this in mind, last 5 years literature on benzimidazole used as anticancer agents has been reviewed and summarized in the paper herein. This review article along with the target of cancer also deal with structure activity relationship of various compounds having benzimidazole ring. [ABSTRACT FROM AUTHOR]

Cisplatin (CP) is one of the most potent chemotherapeutic anti-tumour drugs, and it has been implicated in renal toxicity. Oxidative stress has been proven to be involved in CP-induced toxicity including nephrotoxicity. However, there is paucity of literature involving role of mitochondria in mediating CP-induced renal toxicity, and its underlying mechanism remains unclear. Therefore, the present study was undertaken to examine the antioxidant potential of curcumin (CMN; a natural polyphenolic compound) against the mitochondrial toxicity of CP in kidneys of male rats. Acute toxicity was induced by a single intra-peritoneal injection of CP (6 mg kg−1). We studied the ameliorative effect of CMN pre-treatment (200 mg kg−1) on the toxicity of CP in rat kidney mitochondria. CP caused a significant elevation in the mitochondrial lipid peroxidation (LPO) levels and protein carbonyl (PC) content. Pre-treatment of rat with CMN significantly replenished the mitochondrial LPO levels and PC content. It also restored the CP-induced modulatory effects on altered enzymatic and non-enzymatic antioxidants in kidney mitochondria. We hypothesize that the reno-protective effects of CMN may be related to its predisposition to scavenge free radicals, and upregulate antioxidant machinery in kidney mitochondria. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Scaffold modules known as aminoacyl‐tRNA synthetase (aaRS)‐interacting multifunctional proteins (AIMPs), such as AIMP1/p43, AIMP2/p38 and AIMP3/p18, are important in driving the assembly of multi‐aaRS (MARS) complexes in eukaryotes. Often, AIMPs contain an N‐terminal glutathione S‐transferase (GST)‐like domain and a C‐terminal OB‐fold tRNA‐binding domain. Recently, the apicomplexan‐specific Plasmodium falciparum p43 protein (Pfp43) has been annotated as an AIMP and its tRNA binding, tRNA import and membrane association have been characterized. The crystal structures of both the N‐ and C‐terminal domains of the Plasmodium vivax p43 protein (Pvp43), which is an ortholog of Pfp43, have been resolved. Analyses reveal the overall oligomeric structure of Pvp43 and highlight several notable features that show Pvp43 to be a soluble, cytosolic protein. The dimeric assembly of the N‐terminal GST‐like domain of Pvp43 differs significantly from canonical GST dimers, and it is tied to the C‐terminal tRNA‐binding domain via a linker region. This work therefore establishes a framework for dissecting the additional roles of p43 orthologs in eukaryotic multi‐protein MARS complexes. [ABSTRACT FROM AUTHOR]