A transgene carrying an A2G missense mutation in the SMN gene modulates phenotypic severity in mice with severe (type I) spinal muscular atrophy

5q spinal muscular atrophy (SMA) is a common autosomal recessive disorder in humans and the leading genetic cause of infantile death. Patients lack a functional survival of motor neurons (SMN1) gene, but carry one or more copies of the highly homologous SMN2 gene. A homozygous knockout of the single murine Smn gene is embryonic lethal. Here we report that in the absence of the SMN2 gene, a mutant SMN A2G transgene is unable to rescue the embryonic lethality. In its presence, the A2G transgene delays the onset of motor neuron loss, resulting in mice with mild SMA. We suggest that only in the presence of low levels of full-length SMN is the A2G transgene able to form partially functional higher order SMN complexes essential for its functions. Mild SMA mice exhibit motor neuron degeneration, muscle atrophy, and abnormal EMGs. Animals homozygous for the mutant transgene are less severely affected than heterozygotes. This demonstrates the importance of SMN levels in SMA even if the protein is expressed from a mutant allele. Our mild SMA mice will be useful in (a) determining the effect of missense mutations in vivo and in motor neurons and (b) testing potential therapies in SMA.     

Novel diarylheptanoids as inhibitors of TNF-α production

Synthesis and anti-inflammatory activity of novel diarylheptanoids [5-hydroxy-1-phenyl-7-(pyridin-3-yl)-heptan-3-ones and 1-phenyl-7-(pyridin-3-yl)hept-4-en-3-ones] as inhibitors of tumor necrosis factor-α (TNF-α) production is described in the present article. The key reactions involve the formation of a β-hydroxyketone by the reaction of substituted 4-phenyl butan-2-ones with pyridine-3-carboxaldehyde in presence of LDA and the subsequent dehydration of the same to obtain the α,β-unsaturated ketones. Compounds 4i, 5b, 5d, and 5g significantly inhibit lipopolysaccharide (LPS)-induced TNF-α production from human peripheral blood mononuclear cells in a dose-dependent manner. Of note, the in vitro TNF-α inhibition potential of 5b and 5d is comparable to that of curcumin (a naturally occurring diarylheptanoid). Most importantly, oral administration of 4i, 5b, 5d, and 5g (each at 100 mg/kg) but not curcumin (at 100 mg/kg) significantly inhibits LPS-induced TNF-α production in BALB/c mice. Collectively, our findings indicate that these compounds may have potential therapeutic implications for TNF-α-mediated auto-immune/inflammatory disorders.     

Spinal muscular atrophy: a deficiency in a ubiquitous protein; a motor neuron-specific disease

Spinal muscular atrophy (SMA) is a neurodegenerative disease in humans and the most common genetic cause of infant mortality. The disease results in motor neuron loss and skeletal muscle atrophy. Despite a range of disease phenotypes, SMA is caused by mutations in a single gene, the Survival of Motor Neuron 1 (SMN1) gene. Recent advances have shed light on functions of the protein product of this gene and the pathophysiology of the disease, yet, fundamental questions remain. This review attempts to highlight some of the recent advances made in the understanding of the disease and how loss of the ubiquitously expressed survival of motor neurons (SMN) protein results in the SMA phenotype. Answers to some of the questions raised may ultimately result in a viable treatment for SMA.     

QSAR and Docking Studies on Capsazepine Derivatives for Immunomodulatory and Anti-Inflammatory Activity

Capsazepine, an antagonist of capsaicin, is discovered by the structure and activity relationship. In previous studies it has been found that capsazepine has potency for immunomodulation and anti-inflammatory activity and emerging as a favourable target in quest for efficacious and safe anti-inflammatory drug. Thus, a 2D quantitative structural activity relationship (QSAR) model against target tumor necrosis factor-α (TNF-α) was developed using multiple linear regression method (MLR) with good internal prediction (r² = 0.8779) and external prediction (r² _pred = 0.5865) using Discovery Studio v3.5 (Accelrys, USA). The predicted activity was further validated by in vitro experiment. Capsazepine was tested in lipopolysaccharide (LPS) induced inflammation in peritoneal mouse macrophages. Anti-inflammatory profile of capsazepine was assessed by its potency to inhibit the production of inflammatory mediator TNF-α. The in vitro experiment indicated that capsazepine is an efficient anti-inflammatory agent. Since, the developed QSAR model showed significant correlations between chemical structure and anti-inflammatory activity, it was successfully applied in the screening of forty-four virtual derivatives of capsazepine, which finally afforded six potent derivatives, CPZ-29, CPZ-30, CPZ-33, CPZ-34, CPZ-35 and CPZ-36. To gain more insights into the molecular mechanism of action of capsazepine and its derivatives, molecular docking and in silico absorption, distribution, metabolism, excretion and toxicity (ADMET) studies were performed. The results of QSAR, molecular docking, in silico ADMET screening and in vitro experimental studies provide guideline and mechanistic scope for the identification of more potent anti-inflammatory & immunomodulatory drug.     

Fungal growth promotor endophytes: a pragmatic approach towards sustainable food and agriculture

Agricultural productivity suffers a heavy loss due to plant pathogens, insect pests and various abiotic stresses. Agriculture being the world’s largest economic sector, it is the need of time to find and establish the ideal strategy for sustainable agriculture and improvement in crop growth. Endophytes are microorganisms that asymptomatically grow within the plant tissues without causing any disease to the host. Endophytic fungi live in symbiotic association with plants and play an important role in plant growth promotion, higher seed yield and plants resistant to various biotic, abiotic stresses and diseases. Many are able to produce antimicrobial compounds, plant growth hormones and various agrochemical bioactive metabolites. These mycoendophytes hold enormous potential for the development of eco-friendly and economically viable agricultural products. In this review we focused on the endophytic fungi recovered from different medicinal plants, their active principles involved in plant growth enhancement and the applications of fungal endophytes in agriculture. Moreover, we also discussed about endophytic fungi and their pragmatic approach towards sustainable food and agriculture.     

Limited Phenotypic Effects of Selectively Augmenting the SMN Protein in the Neurons of a Mouse Model of Severe Spinal Muscular Atrophy

The selective vulnerability of motor neurons to paucity of Survival Motor Neuron (SMN) protein is a defining feature of human spinal muscular atrophy (SMA) and indicative of a unique requirement for adequate levels of the protein in these cells. However, the relative contribution of SMN-depleted motor neurons to the disease process is uncertain and it is possible that their characteristic loss and the overall SMA phenotype is a consequence of low protein in multiple cell types including neighboring spinal neurons and non-neuronal tissue. To explore the tissue-specific requirements for SMN and, especially, the salutary effects of restoring normal levels of the protein to neuronal tissue of affected individuals, we have selectively expressed the protein in neurons of mice that model severe SMA. Expressing SMN pan-neuronally in mutant mice mitigated specific aspects of the disease phenotype. Motor performance of the mice improved and the loss of spinal motor neurons that characterizes the disease was arrested. Proprioceptive synapses on the motor neurons were restored and defects of the neuromuscular junctions mitigated. The improvements at the cellular level were reflected in a four-fold increase in survival. Nevertheless, mutants expressing neuronal SMN did not live beyond three weeks of birth, a relatively poor outcome compared to the effects of ubiquitously restoring SMN. This suggests that although neurons and, in particular, spinal motor neurons constitute critical cellular sites of action of the SMN protein, a truly effective treatment of severe SMA will require restoring the protein to multiple cell types including non-neuronal tissue.     

Introgression of Pi2 and Pi5 Genes for Blast (Magnaporthe oryzae) Resistance in Rice and Field Evaluation of Introgression Lines for Resistance and Yield Traits

Blast caused by Magnaporthe oryzae is the most devastating disease causing significant loss in rice production. The destructive nature of the disease is mainly due to the genetic plasticity of M. oryzae which complicates the breeding strategies. Blast can be effectively managed by the deployment of R genes. In this study, broad‐spectrum blast resistance genes Pi2 and Pi5 were introgressed independently into popular but blast susceptible rice variety, Samba Mahsuri (BPT5204) by applying marker‐assisted backcross breeding approach. Tightly linked markers AP5930 for Pi2 and 40N23r for Pi5 gene were used in foreground selection. Background selection helped to identify the lines with maximum recovery of recurrent parent genome (RPG). The RPG recovery in Pi2 introgression lines was up to 90.17 and 91.46% in Pi5 lines. Homozygous introgression lines in BC₃F₄ generation carrying Pi2 and Pi5 gene were field evaluated for blast resistance, yield per se and yield‐related traits. The lines showed resistance to leaf and neck blast in multilocation field evaluation. Improved BPT5204 lines with improvement for blast resistance were on par with original BPT5204 in terms of grain yield and grain features.     

DNA isolation from fresh,dry plant samples with highly acidic tissue extracts

Current DNA isolation methods are limited in their ability to obtain quality and/or quantity DNA from plants, such asEmblica officinalis, Terminalia belerica, andTerminalia chebula, which have low pH and high amounts of secondary metabolites in tissue extracts. Our modified DNA isolation method yields good-quality, high-molecular-weight DNA that is free of contaminants and colored pigments and is suitable for PCR amplification. This method is also useful for isolating DNA from dry powders.     

Polyunsaturated fatty acids: biotechnology

Polyunsaturated fatty acids like EPA and DHA have attracted a great attention due to their beneficial effects on human health. At present, fish oil is the major source of EPA and DHA. Various alternative sources are being explored to get these essential fatty acids. Genes encoding enzymes involved in the biosyntheses of PUFAs have been identified, cloned and gene prospecting becomes a novel method for enhanced PUFA production. Desaturase and elongase genes have important biotechnological appeal from genetic engineering point of view. This review highlights the research and results on such enzymes.     

Efficacy of CIM 1166, a combination of compounds derived from Mentha spp. in alleviating experimental vulvovaginal candidiasis in mice

Candida albicans is yeast that is most often associated with serious fungal infections and can cause fungal diseases in immuno-compromised patients especially patients suffering from AIDS, cancer and cases of organ transplant. Amongst women, candidal vaginitis is predominantly caused by strains of Candida albicans and also remains to be a common problem in immuno-competent or healthy women. A study was undertaken to assess the efficacy of a compound CIM 1166 obtained from plant source which was found to possess promising antimicrobial property under in vitro conditions especially against C. albicans. Taking the lead further, a small animal model utilizing aged Swiss albino females that had parturated at least three times were taken up for model development. Infection (7 × 10⁶ cfu/ml) was instilled into the vagina in a volume of 20 μl for 3 days. Vaginal washings were aseptically collected on day 4th to confirm the establishment of infection following which the treatment was started which continued for the next 5 days through vaginal route. Vaginal washings were collected on 6th day and the colony forming units were enumerated on chloramphenicol incorporated SDA plates. The results indicated that there was a significant decrease in the colony forming units in vaginal washings (8.0 × 10² cfu/ml) of the treated animals as compared to blank control group (6.0 × 10⁴ cfu/ml). The positive control group administered with clotrimazole also showed a recovery from infection with a fungal load of 8.78 × 10² cfu/ml. The study proves the efficacy of CIM 1166 in curing vaginal candidiasis in mice, which can be taken up for formulation development and further studies.