Drinking Water Sources along the Banks of Buriganga River of Bangladesh are Polluted and Possess Serious Health Risks: A Comprehensive In Vivo Analysis

Background

The river Buriganga, one of the major dumping zones of industrial wastes in Bangladesh, is responsible for contaminating the drinking water sources along its length. This study aimed to assess the water quality from these sources by monitoring the changes in hematological, biochemical, and histological parameters caused in healthy rats due to their consumption.

Methods

Using ethylenediaminetetraacetic acid (EDTA) as an anticoagulant agent, hematological and biochemical analyses of Sprague-Dawley rat models were executed in this study. Following blood sampling, the rats were sacrificed, and the heart, lungs, kidneys, liver, and spleen were separated to carry out the histological analysis. Later, to perform the statistical analysis, SPSS, V.25.0 was utilized.

Results

A significant rise (p < 0.02) in body weight was recorded due to increased protein synthesis, inflammations; increased lymphocyte, white blood cell (WBC), and neutrophil count but hemoglobin (20.0 ± 1.39 g/dL vs. 15.25 ± 0.36 g/dL; p) and red blood cell (RBC) count ((6.24 ± 0.45) × 106/µL vs. (5.47 ± 0.34) × 106/µL)) decreased due to infections and hematopoietic stem cell poisoning by pathogens in water samples. Elevated (p < 0.01) serum urea, creatinine, alanine, and aspartate aminotransferase levels indicated kidney malfunction and hepatic tissue necrosis. Histological analysis revealed gross lesions, internal hemorrhages in the brain; inflammations, granulomas, migrating macrophages in the spleen; fibrosis (resulting in hypo-perfusion), and collagen formation in cardiac muscles.

Conclusions

The findings in this study provide comprehensive evidence, based on in vivo analysis, that the water bodies around the Buriganga river are likely to be contaminated with toxic chemicals and microbial entities making them unfit for human consumption.

0023 Neuropeptidergic Regulation of Drosophila Larval Sleep

Introduction

Sleep during early life is thought to be important for brain development. Indeed, disruptions in sleep during development have long-lasting effects on cognitive functioning. Recently, our lab has developed the LarvaLodge platform for monitoring sleep in developing Drosophila larvae. Using this system we can investigate the neural circuits and signals controlling sleep during early neurodevelopmental periods. Neuropeptides play critical roles in regulating many behaviors in both larvae and adult flies.While several neuropeptides modulate sleep in adult flies, it is not known what role neuropeptides play in controlling larval sleep.

Methods

To identify peptidergic neurons that regulate 2nd instar larval sleep, we activated neurons labeled by 34 independent Gal4 driver lines corresponding to 25 different neuropeptide genes using the heat-sensitive cation channel, TrpA1.

Results

Of the 34 Gal4 driver lines, we determined that 2 lines are wake-promoting and 7 lines are sleep-promoting. A subset of these exert effects on sleep without associated changes in wake activity levels. We also observed sleep fragmentation (increase in sleep bout number and decrease in sleep bout length) in 3 lines. Subsequent analysis indicated that manipulation of activity in Diuretic hormone 44 (Dh44)-labeled neurons bidirectionally modulates sleep-wake. Additionally, pan-neuronal knockdown of Dh44 altered sleep duration.

Conclusion

This work indicates that neuropeptidergic signaling modulates sleep during early development and provides a platform to examine how neuropeptidergic regulation of sleep/wake changes throughout the lifespan.

Support

NIH T32

0069 Sleep in Drosophila is Regulated by the Chromatin Remodeling Factor ISWI

Introduction

Sleep is commonly disrupted in patients with neurodevelopmental disorders (NDDs). Despite strong clinical associations between disrupted sleep and other NDD symptoms, we lack an understanding of how these are pathophysiologically related. Drosophila melanogaster exhibit essential characteristics of human sleep and have well-defined neural circuits underlying learning and social behaviors. This represents an ideal system to investigate the mechanistic interaction between disrupted sleep and other behavioral dysfunctions in NDDs.

Methods

We performed a reverse genetic RNAi-based screen targeting Drosophila homologs of human genes within NDD-associated risk loci. Pan-neuronal knockdown of risk genes was achieved using the Gal4-UAS system.

Results

Pan-neuronal knockdown of ISWI led to dramatic deficits in sleep and circadian arrhythmicity in the adult fly. Across species, ISWI and its homologs are ATP-dependent chromatin remodelers that regulate gene expression important for neural differentiation. We found that depleting ISWI also leads to memory and social deficits. ISWI functions during dissociable temporal windows of pre-adult development and in different circuits to establish different adult behaviors. The sleep phenotype associated with ISWI knockdown mapped to a specific population of cells. RNA-Seq of developing brains during the window important for sleep deficits revealed significant transcriptional changes in genes associated with nervous system development, suggesting ISWI acts in the development of sleep regulatory circuits. Finally, mutations in the human homologs of ISWI, SMARCA1/5, have been implicated in NDDs. Expressing either SMARCA1/5 in the setting of ISWI knockdown differentially rescued adult deficits.

Conclusion

Identification of ISWI provides a platform for unraveling pleiotropic behavioral effects from an NDD risk gene. Sleep, circadian rhythms, memory, and social behaviors are affected by ISWI knockdown, and map to different developmental periods and circuits. In addition, SMARCA1/5 differentially rescue adult behaviors, suggesting NDD-causing mutations in these genes may affect different behaviors. Current work aims to determine how human mutations in SMARCA1/5 affect behaviors.

Support

This work was supported by NIH K08 NS090461 (MSK) and T32 HL007953 (NNG), Hearst Foundation Fellowship 2018 (NNG), Burroughs Welcome Career Award for Medical Scientists, March of Dimes Basil O’Connor Scholar Award, and Sloan Research Fellowship (MSK).

Theoretically Guided Analytical Method Development and Validation for the Estimation of Rifampicin in a Mixture of Isoniazid and Pyrazinamide by UV Spectrophotometer

A simple, rapid, economic, accurate, and precise method for the estimation of rifampicin in a mixture of isoniazid and pyrazinamide by UV spectrophotometeric technique (guided by the theoretical investigation of physicochemical properties) was developed and validated. Theoretical investigations revealed that isoniazid and pyrazinamide both were freely soluble in water and slightly soluble in ethyl acetate whereas rifampicin was practically insoluble in water but freely soluble in ethyl acetate. This indicates that ethyl acetate is an effective solvent for the extraction of rifampicin from a water mixture of isoniazid and pyrazinamide. Computational study indicated that pH range of 6.0–8.0 would favor the extraction of rifampicin. Rifampicin is separated from isoniazid and pyrazinamide at pH 7.4 ± 0.1 by extracting with ethyl acetate. The ethyl acetate was then analyzed at λ_max of 344.0 nm. The developed method was validated for linearity, accuracy and precision according to ICH guidelines. The proposed method exhibited good linearity over the concentration range of 2.5–35.0 μg/mL. The intraday and inter-day precision in terms of % RSD ranged from 1.09 to 1.70% and 1.63 to 2.99%, respectively. The accuracy (in terms of recovery) of the method varied from of 96.7 ± 0.9 to 101.1 ± 0.4%. The LOD and LOQ were found to be 0.83 and 2.52 μg/mL, respectively. In addition, the developed method was successfully applied to determine rifampicin combination (isoniazid and pyrazinamide) brands available in Bangladesh.

Role for rapid dendritic protein synthesis in hippocampal mGluR-dependent long-term depression

A hippocampal pyramidal neuron receives more than 10(4) excitatory glutamatergic synapses. Many of these synapses contain the molecular machinery for messenger RNA translation, suggesting that the protein complement (and thus function) of each synapse can be regulated on the basis of activity. Here, local postsynaptic protein synthesis, triggered by synaptic activation of metabotropic glutamate receptors, was found to modify synaptic transmission within minutes.