Effect of Semecarpus anacardium Linn. nut milk extract on rat neutrophil functions in adjuvant arthritis

Neutrophils play an important role in the pathogenesis of rheumatoid arthritis (RA) and various inflammatory conditions, by accumulation and liberation of active proteolytic enzymes. The effect of milk extract of Semecarpus anacardium Linn. nuts (SA) at a dosage of 150 mg kg(-1) body weight day(-1) for 14 days on adjuvant arthritis was studied to gain some insight into this intriguing disease in relation to neutrophil functions. The decreased phagocytic function of neutrophils (phagocytic index and avidity index) found in adjuvant arthritis was significantly increased by the administration of the drug SA. Increased levels of reactive oxygen species (superoxide radical, hydroxyl radical, H2O2 and myeloperoxidase), lysosomal enzymes (acid phosphatase and cathepsin D) and increased accumulation of neutrophils in the joints observed in adjuvant arthritic animals were reverted back to near normal levels by treatment with SA. The results of this study indicate that SA can be considered to be a good therapeutic agent for inflammation and arthritis.     

Restorative Effect of Kalpaamruthaa, an Indigenous Preparation, on Oxidative Damage in Mammary Gland Mitochondrial Fraction in Experimental Mammary Carcinoma

Cancer prevention and treatment using phytochemicals have attracted increased interest. Recent studies have shown that Semecarpus anacardium Linn nut milk extract (SA), a promising antioxidant and anticancer drug, exerts its anticancer effect through reducing or quenching reactive oxygen species under different conditions. The present study examined whether Phyllanthus emblica Linn fruit, rich in vitamin C content synergistically in combination can enhance both the antioxidant and anticancer activity of S. anacardium nut milk extract in 7, 12-dimethyl benz[a]anthracene (DMBA)-induced experimental mammary carcinoma in rat model. Female Sprague Dawley rats of 180 ± 10g were categorized into six groups. Three groups were administered DMBA (25mg/rat, orally) dissolved in olive oil to induce mammary carcinoma. One of these groups received Kalpaamruthaa (KA) (300mg/kg b.wt, orally) and other group received SA (200mg/kg b.wt, orally) for 14 days after 90 days of DMBA induction. A vehicle treated control and drug control groups were also included. The mitochondrial fraction of untreated DMBA-induced mammary gland showed 2.61-fold increase in lipid peroxidation level and abnormal changes in the activities/levels of mitochondrial enzymic (superoxide dismutase, glutathione peroxidase and glutathione reductase) and non-enzymic (glutathione, vitamin C and vitamin E) antioxidants were observed. DMBA treated rats also showed decline in the activities of mitochondrial enzymes such as succinate dehydrogenase, malate dehydrogenase, α-ketoglutarate dehydrogenase and isocitrate dehydrogenase. In contrast, rats treated with Kalpaamruthaa showed normal lipid peroxide level and antioxidant defenses. The results of the present study highlight the improved antioxidant property of KA than sole treatment of S. anacardium nut milk extract.     

A cold-adapted esterase of a novel marine isolate, Pseudoalteromonas arctica: gene cloning, enzyme purification and characterization

A gene encoding an esterase (estO) was identified and sequenced from a gene library screen of the psychrotolerant bacterium Pseudoalteromonas arctica. Analysis of the 1,203 bp coding region revealed that the deduced peptide sequence is composed of 400 amino acids with a predicted molecular mass of 44.1 kDa. EstO contains a N-terminal esterase domain and an additional OsmC domain at the C-terminus (osmotically induced family of proteins). The highly conserved five-residue motif typical for all α/β hydrolases (G × S × G) was detected from position 104 to 108 together with a putative catalytic triad consisting of Ser¹⁰⁶, Asp¹⁹⁶, and His²²⁵. Sequence comparison showed that EstO exhibits 90% amino acid identity with hypothetical proteins containing similar esterase and OsmC domains but only around 10% identity to the amino acid sequences of known esterases. EstO variants with and without the OsmC domain were produced and purified as His-tag fusion proteins in E. coli. EstO displayed an optimum pH of 7.5 and optimum temperature of 25°C with more than 50% retained activity at the freezing point of water. The thermostability of EstO (50% activity after 5 h at 40°C) dramatically increased in the truncated variant (50% activity after 2.5 h at 90°C). Furthermore, the esterase displays broad substrate specificity for esters of short-chain fatty acids (C₂–C₈).     

MiRNAs with Apoptosis Regulating Potential Are Differentially Expressed in Chronic Exercise-Induced Physiologically Hypertrophied Hearts

Physiological cardiac hypertrophy is an adaptive mechanism, induced during chronic exercise. As it is reversible and not associated with cardiomyocyte death, it is considered as a natural tactic to prevent cardiac dysfunction and failure. Though, different studies revealed the importance of microRNAs (miRNAs) in pathological hypertrophy, their role during physiological hypertrophy is largely unexplored. Hence, this study is aimed at revealing the global expression profile of miRNAs during physiological cardiac hypertrophy. Chronic swimming protocol continuously for eight weeks resulted in induction of physiological hypertrophy in rats and histopathology revealed the absence of tissue damage, apoptosis or fibrosis. Subsequently, the total RNA was isolated and small RNA sequencing was executed. Analysis of small RNA reads revealed the differential expression of a large set of miRNAs during physiological hypertrophy. The expression profile of the significantly differentially expressed miRNAs was validated by qPCR. In silico prediction of target genes by miRanda, miRdB and TargetScan and subsequent qPCR analysis unraveled that miRNAs including miR-99b, miR-100, miR-19b, miR-10, miR-208a, miR-133, miR-191a, miR-22, miR-30e and miR-181a are targeting the genes that primarily regulate cell proliferation and cell death. Gene ontology and pathway mapping showed that the differentially expressed miRNAs and their target genes were mapped to apoptosis and cell death pathways principally via PI3K/Akt/mTOR and MAPK signaling. In summary, our data indicates that regulation of these miRNAs with apoptosis regulating potential can be one of the major key factors in determining pathological or physiological hypertrophy by controlling fibrosis, apoptosis and cell death mechanisms.     

Immunohistochemical expression of rabphilin-3A-like (Noc2) in normal and tumor tissues of human endocrine pancreas

Involvement of rabphilin-3A-like (RPH3AL), or Noc2, the potential effector of Ras-associated binding proteins Rab3A and Rab27A in the regulation of exocytotic processes in the endocrine pancreas has been demonstrated in experimental models. Noc2 expression together with other regulatory molecules of the exocytotic machinery in human tissues, however, has not been studied. We evaluated immunohistochemical expression of the key molecules of the exocytotic machinery, Noc2, Rab3A, Rab27A, and RIM2, together with the characteristic islet cell hormones, insulin and glucagon in normal and endocrine tumor tissues of human pancreas. Normal pancreatic islets were stained for all of these proteins and showed strong cytoplasmic localization. A similar pattern of strong cytoplasmic expression of these proteins was observed in the majority of endocrine tumors. By contrast, the exocrine portions of normal appearing pancreas completely lacked Rab27A staining and showed decreased expression of the proteins, Noc2, Rab3A, and RIM2. The staining pattern of Noc2 and Rab27A was similar to the staining pattern of glucagon-producing cells within the islets. The concomitant expression of Noc2 with these molecules suggests that Noc2 may serve as an effector for Rab3A and Rab27A and that it is involved in the regulation of exocytosis of the endocrine pancreas in humans.     

Potential risk modifications of GSTT1, GSTM1 and GSTP1 (glutathione-S-transferases) variants and their association to CAD in patients with type-2 diabetes

Background

Type-2 diabetes mellitus (T2DM) is a major risk factor for coronary artery disease (CAD) resulting in high morbidity and mortality. Glutathione S-transferases (GSTM1, GSTT1 and GSTP1) are known for their broad range of detoxification and in the metabolism of xenobiotics. Recent studies revealed the relationship of GSTs variants with T2DM and CAD. In this case-control study we ascertained the association of GSTs variants in association with the development of CAD in patients with T2DM.

Methods

From the Southern part of India, we enrolled 222 T2DM patients, 290 T2DM patients with CAD and 270 healthy controls matched for age, sex and origin. Serum lipid profiles were measured and DNA was extracted from the blood samples. Multiplex PCR for GSTM1/T1 (null polymorphism) and PCR-RFLP for GSTP1 (105 A > G), were performed for genotyping of study participants. Gene frequency and lipid profiles were statistically analyzed for disease association.

Results

Regression analysis showed that, GSTM1-null genotype is associated with a 2-fold increase (OR = 2.925; 95% CI = 2.078–4.119; P < 0.0001) and GSTT1-null genotype is associated with a 3-fold increase (OR = 3.114; 95% CI = 2.176–4.456; P < 0.0001) to T2DM development. Ile/Val and Val/Val genotypes of GSTP1 also showed a significant risk for T2DM (OR = 1.423, CI = 1.041–1.946; P = 0.027 and OR = 1.829, CI = 1.064–3.142; P = 0.029). Increased odds ratio showed that GSTT1-null genotype had a moderately higher occurrence in T2DM–CAD patients (OR = 1.918, 95% CI = 1.144–3.214; P = 0.014) than T2DM patients without CAD. The level of HDL has significantly decreased in GSTT1-present than in GSTT1-null genotype (43.50 ± 4.10 vs. 45.20 ± 3.90; P = 0.004) when compared with control and T2DM patients. However, LDL level showed a significant increase in GSTT1-null than GSTT1-present genotype (108.70 ± 16.90 vs. 102.20 ± 12.60; P = 0.005). Although the GSTM1-null polymorphism showed no correlation with lipid profiles among T2DM and T2DM with CAD patients, GSTT1-null polymorphism attained a statistical significance for the level of LDL (127 ± 28.20 vs. 134 ± 29.10; P = 0.039) and triglycerides in T2DM with CAD patients (182.10 ± 21.10 vs. 191.20 ± 24.10; P = 0.018).

Conclusion

Our work concludes that GSTM1, GSTT1 and GSTP1 variants might contribute to the development of T2DM and GSTT1 variant alone is involved in the development of T2DM associated CAD complications in the South Indian population.     

Alteration of DMBA-induced oxidative stress by additive action of a modified indigenous preparation--Kalpaamruthaa

The present study investigated the protective efficacy of the novel preparation named as Kalpaamruthaa (KA, includes Semecarpus anacardium Linn nut milk extract (SA), dried powder of Phyllanthus emblica fruit and honey) on the peroxidative damage and abnormal antioxidant levels in the hepatic mitochondrial fraction of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinoma rats. Female Sprague-Dawley rats of weight 180+/-10 g were categorized into six groups. Three groups were administered DMBA (25 mg/rat dissolved in olive oil, orally) to induce mammary carcinoma. One of these groups received KA treatment (300 mg/kg b.wt., orally) and other group received SA (200 mg/kg b.wt., orally) for 14 days after 90 days of DMBA induction. Vehicle-treated control and drug control groups were also included. The hepatic mitochondrial fraction of untreated DMBA rats showed 2.96-fold increase in MDA content when compared to control rats and abnormal changes in the activities/levels of mitochondrial enzymic (superoxide dismutase, glutathione peroxidase and glutathione reductase) and non-enzymic (glutathione, vitamin C and vitamin E) antioxidants were observed. DMBA-treated rats also showed decline in the activities of mitochondrial enzymes such as succinate dehydrogenase, alpha-ketoglutarate dehydrogenase, malate dehydrogenase and isocitrate dehydrogenase. In contrast, rats treated with SA and KA showed normal lipid peroxidation antioxidant defenses and mitochondrial enzymes, thereby showing the protection rendered by SA and KA. Although, KA treatment exhibited more profound effect in inhibiting DMBA-induced oxidative stress than sole SA treatment. Results of the study indicate that the anticarcinogenic activity of KA during DMBA-initiated mammary carcinogenesis is mediated through alteration of hepatic antioxidant status as well as modulation of TCA cycle enzymes. On the basis of the observed results, KA can be considered as a readily accessible, promising and novel cancer chemopreventive agent.     

Molecular phylogeny of Neotropical bioluminescent beetles (Coleoptera: Elateroidea) in southern and central Brazil

Bioluminescence in beetles is found mainly in the Elateroidea superfamily (Elateridae, Lampyridae and Phengodidae). The Neotropical region accounts for the richest diversity of bioluminescent species in the world with about 500 described species, most occurring in the Amazon, Atlantic rainforest and Cerrado (savanna) ecosystems in Brazil. The origin and evolution of bioluminescence, as well as the taxonomic status of several Neotropical taxa in these families remains unclear. In order to contribute to a better understanding of the phylogeny and evolution of bioluminescent Elateroidea we sequenced and analyzed sequences of mitochondrial NADH2 and the nuclear 28S genes and of the cloned luciferase sequences of Brazilian species belonging to the following genera: (Lampyridae) Macrolampis, Photuris, Amydetes, Bicellonycha, Aspisoma, Lucidota, Cratomorphus; (Elateridae) Conoderus, Pyrophorus, Hapsodrilus, Pyrearinus, Fulgeochlizus; and (Phengodidae) Pseudophengodes, Phrixothrix, Euryopa and Brasilocerus. Our study supports a closer phylogenetic relationship between Elateridae and Phengodidae as other molecular studies, in contrast with previous morphologic and molecular studies that clustered Lampyridae/Phengodidae. Molecular data also supported division of the Phengodinae subfamily into the tribes Phengodini and Mastinocerini. The position of the genus Amydetes supports the status of the Amydetinae as a subfamily. The genus Euryopa is included in the Mastinocerini tribe within the Phengodinae/Phengodidae. Copyright © 2013 John Wiley & Sons, Ltd.     

Molecular basis of recognition by Gal/GalNAc specific legume lectins: influence of Glu 129 on the specificity of peanut agglutinin (PNA) towards C2-substituents of galactose

The ability to discriminate between galactose and N- acetylgalactosamine, observed in some lectins, is crucial for their biological activity as well as their usefulness as tools in biology and medicine. However, the molecular basis of differential binding of lectins to these two sugars is poorly understood. Peanut agglutinin (PNA) is one of the few galactose-specific legume lectins which does not bind N- acetylgalactosamine at all and is, therefore, ideal for the study of the basis of specificity towards C-2 substituted derivatives of galactopyranosides. Examination of the three-dimensional structure of PNA in complex with lactose revealed the presence of both a longer loop and bulkier residues in the region surrounding the C-2 hydroxyl of the galactopyranoside ring, which can sterically prevent the accommodation of a bulky substituent in this position. One such residue, is a glutamic acid at position 129 which protrudes into the binding site and perhaps directly obstructs any substitution at the C-2 position. Two mutants in bacterially expressed PNA were therefore constructed. These were E129D and E129A, in which Glu129 was replaced by Asp and Ala, respectively. The specificity of the mutants for galactose, galactosamine, and N- acetylgalactosamine was examined through observing the inhibition of hemagglutination and binding of the lectin to immobilized asialofetuin. The results showed that the affinity of E129A and E129D for C-2-substituted derivatives of the galactose varies. The mutant E129D showed significant binding towards N- acetylgalactosamine, suggesting that the residue Glu 129 is crucial in imparting exclusive galactose-specificity upon PNA. This study not only attempts to provide an explanation for the inability of PNA to accommodate C-2-substituted derivatives at its primary subsite, but also seeks to present a basis for engineering lectins with altered specificities.      

Synthesis of 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives and their screening for antimicrobial and antioxidant properties

Novel 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives have been synthesized using boron trifluoride diethyl etherate catalyzed Diels–Alder reaction. This method presents considerable synthetic advantages in terms of high atom economy, mild reaction condition and good yields. The synthesized compounds have been screened for their antibacterial and antioxidant activities.