Govindaraju Archunan

Flehmen response in bull: role of vaginal mucus and other body fluids of bovine with special reference to estrus.

The present investigation was carried out with a view to evaluate the frequency of Flehmen behaviour in bull in response to body fluids of cows in various stages of the estrous cycle, in the context of estrus detection. The study was performed on free moving bulls under natural conditions. Samples of vaginal mucus, saliva, faeces and milk of pro-estrus, estrus and di-estrus stages collected from donor cows were rubbed individually onto the genital regions of non-estrus animals (dummy cows) and the bulls were observed for 30 min for assessment of Flehmen behaviour. The duration of Flehmen behaviour shown by bulls was maximum towards the dummy cows receiving estrus sample. Such Flehmen behaviour, however, did not occur in bulls in response to the cows receiving samples of other stages. The statistical significance was higher (P < 0.001) in exhibiting repeated Flehmen behaviour towards estrus as compared to those of pro-estrus and di-estrus. Among the various body fluids tested, the exhibition of Flehmen behaviour was significantly higher (P < 0.01) in response to estrus vaginal fluid. No response was observed on dummy cows (control) to which only water was applied on the genital region. The results suggest that vaginal mucus may act as an additional/secondary source along with urine in eliciting copulatary behaviour and executing coitus in bulls during estrus. The results further suggest that in addition to vaginal mucus, other body fluids like saliva, faeces and milk have estrus-related odours and are probably involved in bovine bio-communication.

MicroRNAs -the next generation therapeutic targets in human diseases.

MicroRNAs (miRNAs), an abundant class of ~22-nucleotide non-coding RNAs, regulate the expression of genes at post transcriptional level. MiRNAs are important regulators of eukaryotic gene expression and therefore implicated in a wide range of biological processes. The miRNA-related genetic alterations are possibly more implicated human diseases than currently appreciated. Genetic variants in miRNA target sites, called miRNA genes are identified to be associated with human diseases. This review discusses about the role of micro-RNA genes in various human diseases such as neurodegenerative disorders, cardio-vascular diseases, and metabolic disorders, and how they can be targeted as a new therapeutic tool in future with reference to drug discoveries/ development.

Identification of urinary sex pheromones in female buffaloes and their influence on bull reproductive behaviour.

The present study was carried out to identify the urinary sex pheromones of buffaloes and their role in relation to bull reproductive behaviour. Urinary samples were collected from 12 buffalo heifers at four different phases of estrous cycles. Fourteen compounds were identified throughout the cycle, which included phenol, ketone, alkane, alcohol, amide, acid and aldehyde. Among the 14 chemical profiles, three compounds were only found on the day of estrus, viz. 1-chlorooctane, 4-methylphenol and 9-octadecenoic acid. Behavioural investigation clearly showed that bulls were attracted and exhibited repeated flehmen behaviour towards the 4-methyl phenol. The bulls displayed penile erection and mounting behaviour while exposed to 9-octadecenoic acid. However, the other compound, 1-chlorooctane, did not influence such sexual behaviours. The present results provide evidence that the estrus-specific urinary volatile compounds appear to be sex pheromones which initiate the bulls reproductive behaviour.

Detection of estrus by male mice: Synergistic role of olfactory–vomeronasal system

In rodents, olfactory pathway comprises two distinct systems viz, the main olfactory and vomeronasal systems, both differing in anatomy, physiology and function. The precise role of the main olfactory/vomeronasal system in estrus detection is yet to be explored. Therefore, the present investigation was planned to elucidate the role of main olfactory and vomeronasal system in the estrus discriminating ability of male mice. Female urine samples of proestrus, estrus, metestrus, diestrus, ovarectomized, ovarectomized plus estrogen treated and prepubertal mice were used for the present study. In addition, the urine from intact, castrated and castrated with testosterone treated mice was also tested for odour preference by male mice. The male responders were categorized into three groups namely (a) normal, (b) ZnSO(4)-irrigated and (c) vomeronasal organ (VNO)-ablated. The behavioural responses such as frequency and duration of visits to urine samples were carried out in a Y-maze apparatus to assess odour preference. The normal mice displayed more frequent visits to estrus urine samples than to non-estrus samples. In contrast, ZnSO(4)-irrigated mice showed significant reduction in the frequency of visits towards estrus urine, whereas, the vomeronasal (VNO)-ablated mice did not show any noticeable preference. With regard to the duration of visits the VNO-ablated mice showed significant reduction in visiting time when compared to ZnSO(4)-irrigated mice. This finding indicated that the main olfactory system (MOS) was involved primarily in the attraction from a distance, while the VNO played a major role in close proximity (pre-copulatory behaviour). The males spent less time with the urine of same-sex; however, the response was higher with castrated male urine which was reduced on testosterone treatment indicating that a specific odour in intact male causes aversive behaviour in male. This study provides support to the fact that volatile compounds could also be perceived by VNO, probably when the main olfactory system is in functional state. The study implies that the olfactory-vomeronasal system plays a synergistic role in the detection of estrus.

Protective effect of Gymnema montanum against renal damage in experimental diabetic rats

Gymnema montanum Hook (Asclepiadaceae), is an endemic plant species of India, traditionally used for diabetes and its management. In this experiment, the ethanol extract of G. montanum (GLEt) at a dose of 200mg/kg body weight was tested to evaluate its effect on renal damage in alloxan-induced diabetic rats and the efficacy was compared with standard hypoglycemic drug, glibenclamide (600 microg/kg body weight). The GLEt and glibenclamide were administered orally for 3 weeks and the effects on glucose, insulin, renal markers including urea, creatinine and uric acid, lipid peroxidation markers including thiobarbituric reactive substances (TBARS) and hydroperoxides and antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activities in kidney were studied. In addition, the urinary protein profile was studied using SDS-PAGE. The results indicated that the GLEt significantly normalized the elevated blood glucose, renal markers and lipid peroxidation markers and increased antioxidant levels in diabetic kidney. The diabetic rats excreted large amount of proteins than untreated rats which was normalized during the treatment with GLEt. In conclusion, the GLEt was found to be more effective in reducing oxidative stress, thus confirming the ethnopharmacological use of G. montanum in protecting diabetes and its complications.

A machine learning approach for the identification of odorant binding proteins from sequence-derived properties

BackgroundOdorant binding proteins (OBPs) are believed to shuttle odorants from the environment to the underlying odorant receptors, for which they could potentially serve as odorant presenters. Although several sequence based search methods have been exploited for protein family prediction, less effort has been devoted to the prediction of OBPs from sequence data and this area is more challenging due to poor sequence identity between these proteins.ResultsIn this paper, we propose a new algorithm that uses Regularized Least Squares Classifier (RLSC) in conjunction with multiple physicochemical properties of amino acids to predict odorant-binding proteins. The algorithm was applied to the dataset derived from Pfam and GenDiS database and we obtained overall prediction accuracy of 97.7% (94.5% and 98.4% for positive and negative classes respectively).ConclusionOur study suggests that RLSC is potentially useful for predicting the odorant binding proteins from sequence-derived properties irrespective of sequence similarity. Our method predicts 92.8% of 56 odorant binding proteins non-homologous to any protein in the swissprot database and 97.1% of the 414 independent dataset proteins, suggesting the usefulness of RLSC method for facilitating the prediction of odorant binding proteins from sequence information.

DIAL: a web-based server for the automatic identification of structural domains in proteins.

DIAL is a web server for the automatic identification of structural domains given the 3D coordinates of a protein. Delineation of the structural domains and their exact boundaries are the starting points for the better realization of distantly related members of the domain families, for the rational design of the experiments and for clearer understanding of the biological function. The current server can examine crystallographic multiple chains and provide structural domain solutions that can also describe domain swapping events. The server can be accessed from . The Supplementary data can be accessed from .

Impact of Zoo Visitors on the Fecal Cortisol Levels and Behavior of an Endangered Species: Indian Blackbuck (Antelope cervicapra L.)

This study investigated behavioral activities (resting, moving, aggressive, social, and reproductive behavior) and fecal cortisol levels in 8 individually identified adult male blackbucks during periods of varying levels of zoo visitors (zero, low, high, and extremely high zoo visitor density). This study also elucidated whether zoo visitor density could disturb nonhuman animal welfare. This study analyzed fecal cortisol from the samples of blackbuck by radioimmunoassay and found significant differences (p < .05) for time the animals devoted to moving, resting, aggressive, reproductive, and social behavior on days with high and extremely high levels of zoo visitors. The ANOVA with Duncans Multiple Range Test test showed that the fecal cortisol concentration was higher (p < .05) during the extremely high (137.30 ± 5.88 ng/g dry feces) and high (113.51 ± 3.70 ng/g dry feces) levels of zoo visitor density. The results of the study suggest that zoo visitor density affected behavior and adrenocortical secretion in Indian Blackbuck, and this may indicate an animal welfare problem.

Assessment of dominance hierarchy through urine scent marking and its chemical constituents in male blackbuck Antelope cervicapra, a critically endangered species

In ungulates the process of chemical communication by urinary scent marking has been directly related to reproductive dominance, territorial defense and proximity to resources. The differences in the frequency of urine marking and chemical composition of urine of males Antelope cervicapra before, during and after the dominance hierarchy period were assessed. The variations in the urine marking and its chemical profiles of dominant males (n=9), bachelors (n=5) and sub-adult males (n=5) were compared to find out how the dominance hierarchy influences the confined blackbuck herd under semi-natural captive conditions. The frequency of urine marking is significantly higher (p<0.001) in dominant males. Twenty-eight major constituents were identified in the urine of dominant males (before, during and after the dominance hierarchy period), bachelor and sub-adult males. Among these, three specific compounds namely, 3-hexanone (I), 6-methyl-5-hepten-2-one (II) and 4-methyl-3-heptanone (III) were seen only in dominant males urine during the dominance hierarchy period. Based on the behavioural observation and the unique chemical constituents in the urine, it is concluded that the dominant male scent odor suppresses aggression, scent marking, scent production and territorial patrolling activities of subordinate males, through which the dominant male establish their hierarchy and attains success in reproduction.

Spermidine may decrease ER stress in pancreatic beta cells and may reduce apoptosis via activating AMPK dependent autophagy pathway

The risk for diabetes increases with increasing BMI<25. Insulin resistance is the key factor for type 2 diabetes; studies revealed that endoplasmic reticulum stress is the main factor behind this disease. With increase in ER stress, pancreatic beta cells start to undergo apoptosis, leading to a decline in the pancreatic beta cell population. The ER stress arises due to unfolded protein response. Recently, spermidine get importance for increasing the longevity in most of the eukaryotes including yeast, Caenorhabditis elegans, Drosophila and human peripheral blood mononuclear cells via induction of autophagy pathway. Autophagy is also involved in regulation of scavenging of proteins. One of the major cellular pathways for scavenging the aggregated intracellular protein is autophagy. Hence spermidine can be a candidate for the treatment type 2 diabetes. Autophagy genes are regulated by mTOR (mammalian Target Of Rapamycin) dependent or independent pathway via AMPK. Hence either inhibition of mTOR or activation of AMPK by spermidine will play two crucial roles, first being the activation of autophagy and secondly the reduction of endoplasmic reticulum stress which will reduce beta cell death by apoptosis and thus can be a novel therapeutic candidate in the treatment of insulin resistance in type 2 diabetes and preserving pancreatic beta cell mass.