Pokhraj Guha

Study of the KIR gene profiles and analysis of the phylogenetic relationships of Rajbanshi population of West Bengal, India

The natural killer (NK) cells have distinct receptors called killer cell immunoglobulin-like receptors (KIR) which are responsible for regulating NK cell responses to infections and malignancy. The extensive variations in the number and type of KIR genes can be used as a tool to understand the differentiation of populations and also for tracing genetic background. In this study, we have aimed to analyze the KIR gene polymorphism in the Rajbanshi population of West Bengal, India. To our knowledge this is the first report on the KIR gene polymorphism in the Rajbanshis, a population widely distributed in the Terai and Dooars region of West Bengal, India. Herein, we have studied the gene distribution of 14 KIR genes (KIR3DL1-3DL3, KIR 2DL1-2DL5, 2DS1-2DS5 and 3DS1) and two pseudogenes (KIR3DP1 and 2DP1). The gene frequencies and genotypic frequencies were calculated, based on which statistical analyses were performed. The presence of a considerable number of genotypic profiles suggests substantial diversity in the KIR gene pool of the Rajbanshis in the region studied. Apart from the framework genes (KIR2DL4, 3DL2, 3DL3 and 3DP1) present in all the individuals, the gene frequencies of other KIR genes varied between 0.84 and 0.15. Moreover the KIR polymorphisms of the Rajbanshis were also compared with that of available published data of the populations of other ethnicities. Though the Rajbanshi population showed a tendency to cluster with other Indian population based on KIR gene frequencies, the influence of Tibeto-Burman Lineage on their KIR genotypic profiles cannot be overlooked. Furthermore, evidences from previously published data on Y chromosome haplogroup diversity study on Rajbanshis support the view. Our results will not only help to understand the genetic background of the Rajbanshi population, but also in tracing the population migration events in the North-Eastern part of India and in illustrating the extensive genetic admixture amongst the different linguistic groups of the country and also in KIR-related disease researches.

Environmental selection influences the diversity of TLR genes in ethnic Rajbanshi population of North Bengal Region of India

Background Toll-like receptors are the mediators of the innate immune response to pathogens. In human, this gene family regulates the inflammatory pathways and is associated with the susceptibility to infection. Subjects and methods The distribution and the diversity patterns of TLR genes in Rajbanshi population (n = 85) who are the inhabitants of the Northern part of West Bengal, have been investigated in the present study. PCR-SSP was done for all the ten TLR genes. We have also constructed the phylogenetic tree principal component analysis and genetic distance for all the four populations. Results It has been observed that in Rajbanshi population, the frequency of TLR8 (0.894) is higher and the frequency of TLR2 (0.176) is very low. Dendrogram based analysis, as well as the PCA plot, documented the closeness of Rajbanshi and Gurkha population. However, Rabha is distantly related to Rajbanshi population though evidences suggest their emergence from the same East-Asian lineage. Genetic distances between Rajbanshi–Gurkha and Rajbanshi–Muslim are very much smaller than that of Rajbanshi–Rabha populations. Interpretations & conclusions Therefore, it may be concluded that Rajbanshi, Gurkha and Muslims are very much mixed populations and have genetic closeness due to exposure to similar environmental conditions. On the other hand, the Rabhas strictly follow the endogamy and are restricted to a particular region and therefore maintain considerable distances with the other three populations. The data showed some interesting observations which deviate the contemporary thought in respect to the population genetics.

Analyses of Human and Rat Clinical Parameters in Rheumatoid Arthritis Raise the Possibility of Use of Crude Aloe vera Gel in Disease Amelioration

Rheumatoid Arthritis (RA) is a chronic inflammatory condition affecting the joints causing swelling, stiffness and pain which finally leads to substantial loss of functioning and mobility in its advanced stages. In the present study we have monitored important serological parameters of fifty RA patients and also have discussed the justification of using rat as a model for human RA researches by comparing their respective serological parameters. We have also evaluated the anti-arthritic roles of raw Aloe vera gel and its effects in rat model where arthritis was induced by using Freund’s Complete Adjuvant (FCA). Three essential conclusive statements were derived from the study. Firstly, the six clinical parameters that we have selected for the study namely, RA factor, CRP, ASO, ESR, ceruloplasmin and serum creatinine were all essential for the differential diagnosis of Rheumatoid Arthritis during its early and later stages, RA factor being the most sensitive of all parameters (92% sensitivity). Secondly, this study has supported the use of the rat as a model for designing therapeutic strategies against RA. Lastly, as evident from our study, Aloe vera extracts can be beneficial for the reduction of inflammatory edema and also for the reduction of ceruloplasmin in RA condition in rat model. However, further investigations are necessary for more refined therapeutic usage of Aloe vera for the treatment of RA in human.

Amelioration of CCl4 induced liver injury in swiss albino mice by antioxidant rich leaf extract of Croton bonplandianus Baill.

The progress in industrialization has blessed mankind with a technologically superior lifestyle but poor management of industrial waste has in turn poisoned nature. One such chemical is carbon tetra chloride (CCl4), which is a potent environmental toxin emitted from chemical industries and its presence in the atmosphere is increasing at an alarming rate. Presence of CCl4 in human body is reported to cause liver damage through free radical mediated inflammatory processes. Kupffer cells present in the liver are potentially more sensitive to oxidative stress than hepatocytes. Kuffer cells produced tumor necrosis factor-α (TNF-α) in response to reactive oxygen species (ROS), that might further cause inflammation or apoptosis. In this study hepatoprotective capacity of antioxidant rich extract of Croton bonplandianus Baill. (CBL) was evaluated on CCl4 induced acute hepatotoxicity in murine model. Hydro-methanolic extract of C. bonplandianus leaf was used for evaluation of free radical scavenging activity. Liver cells of experimental mice were damaged using CCl4 and subsequently hepatoprotective potential of the plant extract was evaluated using series of in-vivo and in-vitro studies. In the hepatoprotective study, silymarin was used as a positive control. Antioxidant enzymes, pro-inflammatory markers, liver enzymatic and biochemical parameters were studied to evaluate hepatoprotective activity of Croton bonplandianus leaf extract. Free radical scavenging activity of CBL extract was also observed in WRL-68 cell line. The phytochemicals identified by GCMS analysis were scrutinized using in-silico molecular docking procedure. The results showed that CBL extract have potent free radical scavenging capacity. The biochemical parameters were over expressed due to CCl4 administration, which were significantly normalized by CBL extract treatment. This finding was also supported by histopathological evidences showing less hepatocellularnecrosis, inflammation and fibrosis in CBL and silymarin treated group, compared to CCl4 group. ROS generated due to H2O2 in WRL-68 cell line were normalize in the highest group (200 μg/ml) when compared with control and negative control (CCl4) group. After molecular docking analysis, it was observed that the compound α-amyrin present in the leaf extract of C. bonplandianus has better potentiality to protect hepatocellular damages than the standard drug Silymarin. The present study provided supportive evidence that CBL extract possesses potent hepatoprotective capacity by ameliorating haloalkane induced liver injury in the murine model. The antioxidant and anti-inflammatory activities also affirm the same. The synergistic effects of the phytochemicals present in CBL are to be credited for all the hepatoprotective activity claimed above.

Comparative phytochemical profiling of Clerodendrum infortunatum with some selected medicinal plants predominant in the Sub-Himalayan region of West Bengal.

Abstract Background: The aim of the present study was to quantify the phytochemicals of Clerodendrum infortunatum root and correlate on the basis of phytochemicals present with other medicinal plants belonging to different families. Methods: Various standard biochemical and spectrophotometric methods were employed to study the phytochemical status of the root of C. infortunatum. All the analysis was performed in multiple sets. Various statistical methods like principal component analysis, dendogram, Euclidean distance and correlation study were done to compare the phytochemical profile of C. infortunatum with different selected medicinal plants belonging to different families. Results: Results indicated the presence of various phytochemicals like phenol, alkaloid, flavonoid, tannin, thiamine, riboflavin, etc. Among the estimated phytochemicals, phenol had the highest quantity (65.59±1.26 mg/g) followed by lipid (27.51±0.23 mg/g) and tannin (16.40±0.07 mg/100 g). The phytochemical contents of C. infortunatum are much higher than those of the other reference plants. Conclusions: It may be concluded from the present study that the root of C. infortunatum contains very high amount of phytochemicals which are chiefly responsible for various medicinal properties. Therefore, the presence of the bioactive compounds in high quantity may lead to the potent medicinal value of C. infortunatum root.

Study of genetic diversity of KIR and TLR in the Rabhas, an endogamous primitive tribe of India.

The Rabha tribe is a little known small endogamous population belonging to Indo-mongoloid group of north-eastern India. We have analyzed 16 KIR and 5 TLR gene polymorphisms in the Rabha population of northern West Bengal, India for the first time. The observed frequencies of the KIR genes (except framework and pseudogene loci) ranged between 0.26 (KIR2DS3) and 0.96 (KIR2DL1). Comparisons based on KIR polymorphism have revealed that although the Rabhas are of Indian origin the presence of mongoloid component in their gene pool cannot be denied. The frequencies of the 5 TLR genes ranged between 0.90 (TLR4) and 0.46 (TLR5). TLR variations found in the Rabhas may play a synergistic role in fighting against the bacterial invasions. Our results may contribute to the understanding of (1) genetic background and extent of genetic admixture in the Rabhas, (2) population migration events and (3) KIR-disease-TLR interactions.

Diversity of Killer Cell Immunoglobulin-Like Receptor Genes in the Bengali Population of Northern West Bengal, India

The Indian Subcontinent exhibits extensive diversity in its culture, religion, ethnicity and linguistic heritage, which symbolizes extensive genetic variations within the populations. The highly polymorphic Killer cell Immunoglobulin‐like Receptor (KIR) family plays an important role in tracing genetic differentiation in human population. In this study, we aimed to analyse the KIR gene polymorphism in the Bengali population of northern West Bengal, India. To our knowledge, this is the first report on the KIR gene polymorphism in the Bengalis of West Bengal, India. Herein, we have studied the distribution of 14 KIR genes (KIR3DL1‐3DL3, KIR2DL1‐2DL5, KIR2DS1‐2DS5 AND KIR3DS1) and two pseudogenes (KIR3DP1 and 2DP1) in the Bengalis. Apart from the framework genes (KIR2DL4, 3DL2, 3DL3 and 3DP1), which are present in all the individuals, the gene frequencies of other KIR genes varied between 0.34 and 0.88. Moreover, upon comparing the KIR polymorphism of the Bengalis with the available published data of other world populations, it has been found that the Indo‐European‐speaking Bengalis from the region share both Dravidian and Indo‐Aryan gene pool with considerable influences of mongoloid and European descents. Furthermore, evidences from previously published data on human leucocyte antigen and Y‐chromosome haplogroup diversity support the view. Our results will help to understand the genetic background of the Bengali population, in illustrating the population migration events in the eastern and north‐eastern part of India, in explaining the extensive genetic admixture amongst the different linguistic groups of the region and also in KIR‐related disease researches.

A rapid and efficient DNA extraction protocol from fresh and frozen human blood samples

Different methods available for extraction of human genomic DNA suffer from one or more drawbacks including low yield, compromised quality, cost, time consumption, use of toxic organic solvents, and many more. Herein, we aimed to develop a method to extract DNA from 500 μL of fresh or frozen human blood.