Metabolic and cellular stress responses of catfish, Horabagrus brachysoma (Günther) acclimated to increasing temperatures.

We investigated the metabolic and cellular stress responses in an endemic catfish Horabagrus brachysoma acclimated to ambient (26°C), 31, 33 and 36°C for 30 days. After acclimation, fish were sampled to investigate changes in the levels of blood glucose, tissue glycogen and ascorbic acid, activities of enzymes involved in glycolysis (LDH), citric acid cycle (MDH), gluconeogenesis (FBPase and G6Pase), pentose phosphate pathway (G6PDH), protein metabolism (AST and ALT), phosphate metabolism (ACP and ALP) and energy metabolism (ATPase), and HSP70 levels in various tissues. Acclimation to higher temperatures (33 and 36°C) significantly increased activities of LDH, MDH, ALP, ACP, AST, ALT and ATPase and blood glucose levels, whereas decreased the G6PDH enzyme activity and, tissue glycogen and ascorbic acid. Results indicated an overall increase in the carbohydrate, protein and lipid metabolism implying increased metabolic demands for maintaining homeostasis in fish acclimated to higher temperatures (33 and 36°C). We observed tissue specific response of HSP70 in H. brachysoma, with significant increase in gill and liver at 33 and 36°C, and in brain and muscle at 36°C, enabling cellular protection at higher acclimation temperatures. In conclusion, H. brachysoma adjusted metabolic and cellular responses to withstand increased temperatures, however, these responses suggest that the fish was under stress at 33°C or higher temperature.

Environmental propagation of noise in mines and nearby villages: A study through noise mapping.

BACKGROUND: Noise mapping being an established practice in Europe is hardly practiced for noise management in India although it is mandatory in Indian mines as per guidelines of the Directorate General of Mines Safety (DGMS). As a pilot study, noise mapping was conducted in an opencast mine with three different models; one based on the baseline operating conditions in two shifts (Situation A), and two other virtual situations where either production targets were enhanced by extending working hours to three shifts (Situation B) or only by increased mechanization and not changing the duration of work (Situation C). METHODS: Noise sources were categorized as point, line, area, and moving sources. Considering measured power of the sources, specific meteorological and geographical parameters, noise maps were generated using Predictor LimA software. RESULTS: In all three situations, Lden values were 95 dB(A) and 70-80 dB(A) near drill machine and haul roads, respectively. Noise contours were wider in Situation C due to increase in frequency of dumpers. Lden values near Shovel 1 and Shovel 2 under Situation B increased by 5 dB and 3 dB, respectively due to expansion of working hours. In Situation C, noise levels were >82 dB(A) around shovels. Noise levels on both sides of conveyor belts were in the range of 80-85 dB(A) in Situations A and C whereas it was 85-90 dB(A) in Situation B. Near crusher plants, it ranged from 80 to 90 dB(A) in Situations A and C and between 85 and 95 dB(A) in Situation B. In all situations, noise levels near residential areas exceeded the Central Pollution Control Board (CPCB) limits, i.e., 55 dB(A). CONCLUSIONS: For all situations, predicted noise levels exceeded CPCB limits within the mine and nearby residential area. Residential areas near the crusher plants are vulnerable to increased noise propagation. It is recommended to put an acoustic barrier near the crusher plant to attenuate the noise propagation.

p53 dependent apoptotic cell death induces embryonic malformation in Carassius auratus under chronic hypoxia.

Hypoxia is a global phenomenon affecting recruitment as well as the embryonic development of aquatic fauna. The present study depicts hypoxia induced disruption of the intrinsic pathway of programmed cell death (PCD), leading to embryonic malformation in the goldfish, Carrasius auratus. Constant hypoxia induced the early expression of pro-apoptotic/tumor suppressor p53 and concomitant expression of the cell death molecule, caspase-3, leading to high level of DNA damage and cell death in hypoxic embryos, as compared to normoxic ones. As a result, the former showed delayed 4 and 64 celled stages and a delay in appearance of epiboly stage. Expression of p53 efficiently switched off expression of the anti-apoptotic Bcl-2 during the initial 12 hours post fertilization (hpf) and caused embryonic cell death. However, after 12 hours, simultaneous downregulation of p53 and Caspase-3 and exponential increase of Bcl-2, caused uncontrolled cell proliferation and prevented essential programmed cell death (PCD), ultimately resulting in significant (p<0.05) embryonic malformation up to 144 hpf. Evidences suggest that uncontrolled cell proliferation after 12 hpf may have been due to downregulation of p53 abundance, which in turn has an influence on upregulation of anti-apoptotic Bcl-2. Therefore, we have been able to show for the first time and propose that hypoxia induced downregulation of p53 beyond 12 hpf, disrupts PCD and leads to failure in normal differentiation, causing malformation in gold fish embryos.

LC-MS/MS as a tool for identification of bioactive compounds in marine sponge Spongosorites halichondriodes (Dendy 1905).

The sensitivity, specificity and selectivity of liquid chromatography/mass spectrometry tandem mass spectrometry (LC-MS/MS) make it an essential tool for the characterization and identification of low molecular compounds such as fatty acids, sterols, cholastane derivatives, nucleosides etc. In the current work, the marine sponge Spongosorites halichondriodes (order Halichondrida, Family Halichondriidae); a particularly rich source of cytotoxic compounds is studied for the initial characterization of bioactive compounds. The composition of ethyl acetate and butanol extracts were subjected to LC-MS and LC-MS/MS. Many novel sterol derivatives compounds which were not reported in any marine sponge mainly belonged to the group of C25-C28 saturated and unsaturated esters like 3ß, 4ß, 7α, 12α-tetrahydroxy-5ß-cholan-24-oic acid methyl ester, 7 α, 12 ß-dihydroxy-5 ß-cholan24-oic acid methyl ester, novel isocoumarin citrinolactone A, a triterpenoid glycyrrhetinic acid as well as other unknown compounds in this species such as nucleoside inosine was identified. Other compound investigated was 3ß, 6ß, 7α-trihydroxy-5ß-cholan-24-oic acid methyl ester. All the sterol ester derivatives are reported here for the first time in marine sponge belonging to family Halichondriidae. However, the literature report supports the occurrence of 3ß-hydroxy sterols which is considered as a biomarker for this family.

Influence of acclimation temperature on the induction of heat-shock protein 70 in the catfish Horabagrus brachysoma (Günther).

Every organism responds to heat stress by synthesizing a group of evolutionarily conserved proteins called the heat-shock proteins (HSPs) that, by acting as molecular chaperones, protect the cell against the aggregation of denatured proteins and play a significant role in adaptation to temperature. The present study aimed to investigate the critical thermal maxima (CTMax) and the expression of HSP70 in different tissues (gill, brain, muscle and liver) of an endemic catfish Horabagrus brachysoma acclimated at either 20 or 30°C for 30 days. To understand the HSP70 response, fish acclimated to the two temperatures were exposed to preset temperatures (26, 30, 34, 36 and 38°C for 20°C acclimated fish and 32, 34, 36, 38 and 40°C for 30°C acclimated fish) for 2 h, followed by 1 h recovery at their respective acclimation temperatures. The HSP70 levels in the gill, brain, muscle and liver tissues were determined by Western blotting of one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis. A significant (P < 0.05) increase in the CTMax values was observed for fish acclimated at 30°C (41.86 ± 0.39°C) than those acclimated at 20°C (39.13 ± 0.18°C). HSP70 was detected in all the tissues with the highest level in the liver followed by intermediate levels in muscle and brain, and lowest level in gill tissue, irrespective of the acclimation temperatures (20 or 30°C). The HSP70 levels were significantly higher (P < 0.05) in the tissues of fish acclimated at 30°C than those acclimated at 20°C. The mean induction temperature of HSP70 in all the tissues of fish acclimated at either 20 or 30°C was 30 and 34°C, respectively. The optimum temperature for HSP70 induction in all the tissues of fish acclimated at 20°C was 36°C, whereas for fish acclimated at 30°C was 36°C for gill and 38°C for brain, muscle and liver. Decreased levels of HSP70 were noted in all the tissues of fish when exposed to temperatures that exceeded the optimum temperatures for HSP70 inductions. Overall results indicated that acclimation temperature influences both temperature tolerance and induction of HSP70 in H. brachysoma.

Haemato-biochemical and immuno-pathophysiological effects of chronic toxicity with synthetic pyrethroid, organophosphate and chlorinated pesticides in broiler chicks.

Haemato- biochemical and immuno-pathophysiological changes following feeding of broiler chicks with 20 ppm fenvalerate (synthetic pyrethroid, SP), 2 ppm monocrotophos (organophosphate, OP) and 2 ppm endosulfan (chlorinated hydrocarbon, CH) were studied. Four groups of broiler birds (30 each) were fed poultry mash without (control) or mixed with pesticides for 8 weeks. Blood glucose, serum globulin and acetyl cholinesterase (AChE) activity level were decreased (P<0.01) in all treated groups compared to control, but not the serum albumin and BUN. The total ATPase activity was enhanced (P<0.01) in fenvalerate and monocrotophos than birds in control group. Body weight, total erythrocyte count, packed cell volume, haemoglobin, eosinophil and monocyte count did not show any changes. Total leucocytes and T-lymphocyte count was lower (P<0.01) in all treated groups as compared to control group. B-cell count (P<0.01), mean 2-4-dinitrofluorobenzene (DNFB) dermal sensitivity score and splenic indices from graft vs. host reaction (P<0.05) were decreased in fenvalarate and endosulfan but the values for monocrotophos were intermediate between control and other treated groups. Pesticide intoxication reduced nitroblue tetrazolium (NBT) positive cells (active splenic macrophages) (P<0.05) and spleen weight (P<0.01). Whereas bursal weight was reduced only with endosulfan, thymic weight was reduced on endosulfan and fenvalerate-treated feed. Microscopic examination of these organs further revealed atrophy/hypoplasia, decrease in the size of follicles with depletion of lymphocytes and haemorrhages in thymus. The study concludes that the chronic exposure of chicks to small amount of SP, OP and CH pesticide leads to deleterious effects on metabolism and immune system of birds.

Pathophysiological effects of chronic toxicity with synthetic pyrethroid, organophosphate and chlorinated pesticides on bone health of broiler chicks.

This experiment evaluated effects following chronic toxicity with 20 ppm fenvalerate (synthetic pyrethroid), 2 ppm monocrotophos (organophosphate) and 2 ppm endosulfan (chlorinated hydrocarbon) on bone health of broiler chicks. A total of 120 chicks were divided equally into 4 groups and were fed poultry mash without (control) or mixed with different pesticides for 8 weeks. Body mass, serum calcium and phosphorus levels were unaffected due to pesticides treatment. However, increase an (p < 0.01) in serum alkaline phosphatase activity was noted and serum total protein decreased (p < 0.01) in all treated groups. Roentogenography revealed destructive changes in the upper part of the femur in the monocrotophos group. Endosulfan intoxicated chicks had increased numbers of trabeculae in the medullary cavity. Microscopic alterations of the costochondral junction in intoxicated chicks were similar. The zones of proliferating, maturing and degenerating, and calcifying cartilage cells were reduced in width and the metaphysis in treated birds showed a reduced number of cartilage cells and thinner trabeculae. Due to toxicity, the capillary scaffolding of the degenerating cartilage cells was reduced and a larger number of transverse trabeculae could be seen in the metaphysis. Appositional bone growth studied by the tetracyclicline labeling technique indicated decreased active osteons.