Professor
Dean R&D
palok.aichniser.ac.in
+91-674-2494133
Ph.D. (Saha Institute of Nuclear Physics)
Thesis topic: studied the role of bivalent magnesium ions on the mode of action of antitumor antibiotics, Mithramycin and Chromomycin.
PhD: Biophysics
PDF: Biophysics/Molecular Dynamics/Molecular Biology/LASER instrumentation
Scientist @ VIDO: Innate Mucosal Immunity
Faculty @ NISER: Role of Microbiome-Gut-Adipose-Brain Axis on innate mucosal immunity
@ NISER (since July 2009)
Importance of Microbial Diversity on Health: Perhaps the Best Tool to Intervene in Emerging and Continuing Diseases. Sohini Mukhopadhyay, Sunaina Sunaina, Tanuja Mohanty, Ankita Das, Arka Jyoti De, Isha Dwivedi and Palok Aich. In Microbial Diversity in the Genomic Era: Functional Diversity and Community Analysis. SECOND EDITION (2024). Academic Press, Elsevier. Ed by Surajit Das and Hirak Ranjan Dash.
Panda, S. S., Behera, B., Ghosh, R., Bagh, B., & Aich, P. (2024). Antibiotic induced adipose tissue browning in C57BL/6 mice: An association with the metabolic profile and the gut microbiota. Life Sciences, 340, 122473. https://doi.org/10.1016/j.lfs.2024.122473
Uday Pandey, Subodh Tambat and Palok Aich. Postnatal 14D is the key window for mice intestinal development- An insight from age-dependent antibiotic-mediated gut microbial dysbiosis study. Advanced Biology 2023 (in press). DOI: 10.1002/adbi.202300089
Panda, S.S.; Nayak, A.; Shah, S.; Aich, P. A Systematic Review on the Association between Obesity and Mood Disorders and the Role of Gut Microbiota. Metabolites 2023,13,488. https://doi.org/ 10.3390/metabo13040488
Singh, Dhyanendra, Shalini Pandey, Arindam Ghosh, and Palok Aich. "Effects of Constant Darkness on Behaviour and Physiology of Male and Female Mice." European Journal of Neuroscience 57, no. 9 (2023): 1498-1515. Accessed April 28, 2024. https://doi.org/10.1111/ejn.15972.
Singh, Dhyanendra, Abhilash Preetam Ambati, and Palok Aich. "Sex and Time: Important Variables for Understanding the Impact of Constant Darkness on Behavior, Brain, and Physiology." Neuroscience 519, (2023): 73-89. Accessed April 28, 2024. https://doi.org/10.1016/j.neuroscience.2023.03.016..
Sohini Mukhopadhyay, Tanya Pattnaik, and Palok Aich. A deeper understanding of the gut microbiota of different human races in search of disease-specific microbial and metabolic biomarkers. Microenvironment & Microecology Research | 2022, Vol. 4 | Issue (4): No.18 https://doi.org/10.53388/MMR2022018
Mukhopadhyay, S., Ray, P. and Aich, P. A comparative analysis of gut microbial dysbiosis by select antibiotics and DSS to understand the effects of perturbation on the host immunity and metabolism. Life Sciences (2022), Volume 312, 1 January 2023, 121212 https://doi.org/10.1016/j.lfs.2022.121212
Chu, L.M., Karunanayake, C., Aich, P. et al. Association between liver enzymes and metabolic syndrome in Canadian adults: results from the Canadian health measures survey - cycles 3 &4. J Diabetes Metab Disord 21, 1699–1708 (2022). https://doi.org/10.1007/s40200-022-01124-x https://doi.org/10.1007/s40200-022-01124-x
Mukhopadhyay, S. and Aich, P. (2022). Cost-Effective Method for gDNA Isolation from the Cecal Content and High Yield Procedure for RNA Isolation from the Colonic Tissue of Mice. Bio-protocol 12(15): e4484. DOI: 10.21769/BioProtoc.4484.
Impact of sodium-glucose cotransporter-2 inhibitors on liver steatosis/fibrosis/inflammation and redox balance in non-alcoholic fatty liver disease Francesco Bellanti, Aurelio Lo Buglio, Michał Dobrakowski, Aleksandra Kasperczyk, Sławomir Kasperczyk, Palok Aich, Shivaram P Singh, Gaetano Serviddio, Gianluigi Vendemiale. World J Gastroenterol 2022 July 14; 28(26): 3243-3257. DOI: 10.3748/wjg.v28.i26.3243
Effects of starch-rich or fat-rich diets on metabolism, adiposity, and glycemia in immune-biased, C57BL/6 and BALB/c mice. Raktim Mukherjee, Shalini Pandey, Arindam Ghosh, and Palok Aich (2022). J Nutritional Biochemistry Volume 108,109086, ISSN 0955-2863, https://doi.org/10.1016/j.jnutbio.2022.109086.
Postnatal intestinal mucosa and gut microbial composition develop hand in hand: A mouse study. Uday Pandey and Palok Aich. (in press, Biomedical Journal 2022), https://doi.org/10.1016/j.bj.2022.03.004
Differential colitis susceptibility of Th1- and Th2-biased mice: A multi-omics approach. Sohini Mukhopadhyay, Subha Saha, Subhayan Chakraborty, Punit Prasad, Arindam Ghosh, Palok Aich. PLoS One. Published: March 9, 2022, https://doi.org/10.1371/journal.pone.0264400
Microbiota transplantation from younger to older mice could restore lost immunity to effectively clear salmonella infection in Th2-biased BALB/c mice, Salila Pradhan, Pratikshya Ray, Palok Aich, Life Sciences 2021, 120201, ISSN 0024-3205. https://doi.org/10.1016/j.lfs.2021.120201. (https://www.sciencedirect.com/science/article/pii/S0024320521011887)
Predictive Biomarkers of Cardiovascular Disease in Adult Canadian Population. Punam Pahwa, Luan Chu, Chandima Karunanayake, Palok Aich, Markus Hecker, Anurag Saxena, Philip Griebel, Soumya Niyogi. Journal of Diabetes & Metabolic Disorders 2021, 20,1199–1209.
The starch-rich diet causes lipidemia while the fat-rich diet induces visceral adiposity, meta-inflammation, and Insulin resistance differentially in immune-biased mouse strains. Raktim Mukherjee & Palok Aich. Food Biosciences 2021, 42, August 2021, https://doi.org/10.1016/j.fbio.2021.101136 .
Effects of two potential probiotic Lactobacillus bacteria on adipogenesis in vitro. Dipanjan Guha, Raktim Mukherjee & Palok Aich. Life Sciences 2021, 278, https://doi.org/10.1016/j.lfs.2021.119538 . [equal contribution: DG & RM].
Vancomycin induced changes in host immunity and behavior: Comparative genomic and metagenomic analysis in C57BL/6 and BALB/c mice. Pratikshya Ray, Uday Pandey, Debasmita Das, and Palok Aich. Digestive Diseases and Sciences 2021, https://rdcu.be/ccWpM
Secretory clusterin promotes oral cancer cell survival via inhibiting apoptosis by activation of autophagy in Akt/mTOR/ULK1 dependent pathway. Prajna P. Naik, PhD; Debasna P. Panigrahi; Kewal K. Mahapatra; Srimanta Patra; Prakash P. Praharaj; Chandra S. Bhol; Sarbari Saha; Aditya K. Panda; Krupasindhu Panda; Subhankar Paul; Palok Aich; Samir K Patra, and Sujit K Bhutia. Life Sciences 2020, https://doi.org/10.1016/j.lfs.2020.118722
Pratikshya Ray, Uday Pandey and Palok Aich. Comparative analysis of beneficial effects of Vancomycin treatment on Th1- and Th2-biased mice and the role of gut microbiota. J Applied Microbiology 2020,. https://doi.org/10.1111/jam.14853
Dipanjan Guha, Raktim Mukherjee and Palok Aich. Macrophage plays important role in cortisol and serotonin-induced adipogenesis in vitro, In Vitro Cellular & Developmental Biology - Animal. 2020; doi:10.1007/s11626-020-00482-1 [equal contribution: DG & RM] [published online ahead of print, 2020 Aug 5].
Rinku Pramanick, Niranjan Mayadeo, Himangi Warke, Shahina Begum, Palok Aich, and Clara Aranha. Vaginal microbiota of asymptomatic bacterial vaginosis and vulvovaginal candidiasis: Are they different from normal microbiota? Microbial Pathogenesis 2019, 134, 103599. https://www.ncbi.nlm.nih.gov/pubmed/31212037
Dipanjan Guha, Arka Banerjee, Raktim Mukherjee, Biswaranjan Pradhan, Maria Peneva, Georgi Aleksandrov, Sujit Suklabaidya, Shantibhushan Senapati and Palok Aich. A Probiotic formulation containing Lactobacillus bulgaricus DWT1 inhibits tumor growth by activating pro-inflammatory responses in macrophages. Journal of Functional Foods 2019, 56, 232-245. https://doi.org/10.1016/j.jff.2019.03.030
J. Tomporowski, J.M. Heer, B. Allan, S. Gomis, P. Aich, Carbon nanotubes significantly enhance the biological activity of CpG ODN in chickens, International Journal of Pharmaceutics 2019, 561, 135-147. https://doi.org/10.1016/j.ijpharm.2019.02.040
Naik, A., Pandey, U., Mukherjee, R., Mukhopadhyay, S., Chakraborty, S., Ghosh, A., Aich, P. Lactobacillus rhamnosus GG reverses mortality in neonatal mice against Salmonella challenge. Toxicology Research (RSC) 2019, DOI: https://doi.org/10.1039/C9TX00006B
Priyadarshini, S., Pradhan, B., Griebel, P., and Aich, P. Cortisol regulates immune and metabolic processes in murine adipocytes and macrophages through HTR2c and HTR5a serotonin receptors. ​Eur. J Cell Biol. 2018, 97(7), 483-492, https://doi.org/10.1016/j.ejcb.2018.07.004
Priyadarshini, S., Pradhan, B., and Aich, P. Role of Murine macrophage in temporal regulation of cortisol and serotonin induced adipogenesis in pre-adipocytes when grown together. Biol Open 2018, http://bio.biologists.org/content/biolopen/7/8/bio034629.full.pdf?with-ds=yes
Pradhan, B., Guha, D., Naik, A. K., Banerjee, A., Tambat, S., Chawla, S., Senapati, S., and Aich, P. , Probiotics L. acidophilus and B. clausii Modulate Gut Microbiota in Th1- and Th2-Biased Mice to Ameliorate Salmonella Typhimurium-Induced Diarrhea. Probiotics Antimicrob Proteins, 2018. DOI:10.1007/s12602-018-9436-5; https://link.springer.com/article/10.1007/s12602-018-9436-5
Debakanta Mishra, Debakanta Mishra, Kaibalya R. Dash, Preetam Nath, Prasant K. Parida, Subhendu Panigrahi, Chittaranjan Khatua, Suryakant Parida, Sambit K. Behera, Shivaram P. Singh, Palok Aich. Temporal Trends in the Etiology of Chronic Liver Disease in Coastal Eastern Odisha, Journal of Clinical and Experimental Hepatology, Volume 7, Supplement 2, 2017, Page S93DOI: http://dx.doi.org/10.1016/j.jceh.2017.05.168
Pradhan B, Guha D, Murmu KC, Sur A, Ray P, Das D, Aich P. Comparative efficacy analysis of anti-microbial peptides, LL-37 and indolicidin upon conjugation with CNT, in human monocytes. J Nanobiotechnology 15, 2017, 44 https://www.ncbi.nlm.nih.gov/pubmed/28606090
Biswaranjan Pradhan, David A. Datzkiw and Palok Aich (2016). Gut 
microbiota and health: a review with focus on metabolic and immunological disorders and microbial remediation. Biomedical Reviews 27. 2016, 1-17. 
http://journals.mu-varna.bg/index.php/bmr/issue/view/171
Front cover: Change in healthy microbial composition leads to dysbiosis (red arrows) and is associated with obesity, diabetes, colorectal cancer, irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) and Clostridium difficile infections (CDI). Prebiotics, probiotics and fecal microbial transplantation (FMT) remediate microbial symbiosis (green arrows) and return the microbial composition to a healthy state. From the Review of Pradhan et al, Biomedical Reviews 27. 2016, 1-17. 
 http://journals.mu-varna.bg/index.php/bmr/issue/view/171
Biswaranjan Pradhan, Dipanjan Guha, Pratikshya Ray, Debashmita Das, and Palok Aich. Comparative Analysis of the Effects of Two Probiotic Bacterial Strains on Metabolism and Innate Immunity in the RAW 264.7 Murine Macrophage Cell Line. Probiotics Antimicrob Proteins 2016: 1-12. 10.1007/s12602-016-9211-4 https://link.springer.com/article/10.1007/s12602-016-9211-4
Sushri Priyadarshini and Palok Aich. Understanding effects of Psychological Stress on physiology and disease through human stressome - An integral algorithm. Current Bioinformatics 2016, 11(2), 277- 290 https://www.ingentaconnect.com/content/ben/cbio/2016/00000011/00000002/art00017
Shivaram Singh, Ayaskanta Singh, Debasis Misra, Bijay Misra, Girish Pati, Sanjib Kar, Manas Panigrahi, Pallavi Bhuyan, Kaumudi Pattnaik, Chudamani Meher, Omprakash Agrawal, Niranjan Rout, Palok Aich. Risk factors associated with the development of non-alcoholic fatty liver disease in Indians: A case-control study. Journal of Clinical and Experimental Hepatology 2015, 5(4), 295-302 https://www.ncbi.nlm.nih.gov/pubmed/26900270
Abhinav Sur, Biswaranjan Pradhan, Arka Banerjee & Palok Aich. (2015) Immune activation efficacy of indolicidin is enhanced upon conjugation with carbon nanotubes and gold nanoparticles. PLoS One 10 e0123905. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4398554/
P. Sood, S. Priyadarshini & P. Aich. Estimation of Psychological Stress in Humans: A Combination of Theory and Practice. PLoS ONE 2013, 8, e63044.). http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0063044
S. Priyadarshini and P. Aich. Effects of psychological stress on innate immunity and metabolism in humans: a systematic analysis. PLoS One 2012, 7: e43232 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3446986/
Paul D Hodgson, Palok Aich, Joseph Stookey, Yurij Popowych, Andrew Potter, Lorne Babiuk, and Philip J Griebel. Stress significantly increases mortality following a secondary bacterial respiratory infection. Veterinary Research 2012, 43, 21. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3348069/
P. Sood P, S. Priyadarshini, P. Aich. Psychological stressors as interventions: Good out of the evil. Front Biosci (Schol Ed) 2012, 4: 43-60. https://www.ncbi.nlm.nih.gov/pubmed/22202042
B. Kumar, A. Manuja, P. Aich. Stress and its impact on farm animals.Front Biosci (Elite Ed) 2012, 4: 1759-1767. https://www.bioscience.org/2012/v4e/af/496/fulltext.htm
A. Dwivedy and P. Aich. Importance of Innate Mucosal Immunity and promises it holds. International Journal of General Medicine 2011. 4, pp:299-311 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3085239/
Alison Thompson, Elaine Van Moorlehem, and P. Aich. Probiotic-Induced Priming of Innate Immunity to Protect Against Rotaviral Infection. Probiotics and Antimicrobial Proteins 2010: Volume 2, Issue 2, Page 90 https://link.springer.com/article/10.1007/s12602-009-9032-9
For complete publications, please click here
Palok Aich on ResearchGate (Click here)
Trillions of microbes (bacteria, viruses, fungi, and parasites) reside on various surfaces (mucosa, skin, etc.). An ideal system of mutualism as long as both parties (host and microbes) are happy and benefit. Any perturbation (antibiotic treatment, altered diets, body clock, dark-light balance, diseases, etc.) can endanger the host's health. The questions are, a) How is balance maintained (do we need a holistic understanding of body energy balance, endocrine dynamics, and gut-brain communication) and b) to achieve the required balance, do we need all those whopping amounts of microbes (overtly bacteria, to be precise gut bacteria as that is the largest in number and gut is the major reservoir).
My lab currently tries to understand a) various ways to induce gut bacterial dysbiosis and its consequence on the gut-adipose-brain axis and b) the role of the gut microbiome (bacteria) in various diseases (diabetes, obesity, NAFLD, and PD).
We work with animals (mice models, Th1 and Th2, and soon with select Knock Outs), humans, and tissue organoids (gut epithelium, spheroids, and perhaps soon with some brain organoids). The lab also uses various bioinformatic tools to map the microbiome on the host metabolome. The Aichlab utilizes regression-based data science methodologies of AI-ML and uni- and multivariate statistics, clustering, classification, and grouping of similar and dissimilar datasets, and network-based mathematical modeling of lab-generated data in metabolism, metagenomics, cell biology, immunology, microbiology, and neuroscience.
My lab also attracted Industry funding to establish methodologies to predict microbiome from the host metabolic profile. The people in the lab get a flavor of both academia and industry environment and training. I encourage young researchers to develop skills to be an entrepreneur.
Evolution of the work that I initiated @ NISER. My primary goal is to establish an effective way to strengthen innate mucosal immunity. The modern-day world requires more work than play. At the same time, such demand puts us under various stressors (cause of stress) with the potential to perturb homeostasis. By homeostasis, I try to imply a process where physiologically, we try to restore normalcy by adjusting the parameters of several physiological functions of a system. A few of the lab's interests, to begin with, were a) how do we achieve the restoration, b) how are balancing acts performed among different physiological events, such as immunity and metabolism? My research group developed methodologies to quantify the psychological stress status of individuals, correlating stress with disease susceptibility (e.g., metabolic syndromes and infectious diseases) and how we can prime innate immunity to prevent such infections. To prime immunity, we selected probiotics and host defense peptides. We also tried to enhance the efficacy of these immune modulators with nano-materials. The initial leads from our work prompted me to understand the gut microbiome's role on the gut-adipose-brain axis. This approach is critical in understanding health and physiology to establish intrinsic intervention for the host.
My focus is on understanding the role of the gut microbiota in modulating innate immunity and metabolism. We try to understand the effects of the gut microbiome on the brain and the effects of psychological stress (as a perturbation to brain function) on the gut microbiota. We try to understand the reversibility of the Microbiome-Gut-adipose-Brain axis. The study is being done in differentially immune-biased mice models. Human studies are also being planned with Industry sponsorship. We are also developing different organoids (mini-organ). The gut epithelium organoid of mouse origin is already established in the laboratory. We are now initiating adipose and brain organoids.
We also analyze existing data to correlate metabolome and gut microbiome in various human metabolic disorders to develop personalized probiotics using bioinformatic and clinical studies.
Hundreds of trillions (1014) of tiny creatures call our body home, including bacteria, viruses, fungi, and others. They're not always bad news; our health depends on having a thriving collection of microbes. Our results show that the correlation between individuals' genomic and metagenomic (especially for gut microbiota) features might lead to a better understanding of physiology and better sustenance of health. There are microbes everywhere in our bodies. Some coat our skin (yes, even after washing our hands). Others populate the inside of our mouth (some forming tooth-destroying plaque, and others that are harmless or beneficial). According to some estimates, our large intestine is the largest repository of microbes - about three pounds' worth. If we could count the number of individual bacterial cells, we would find that they vastly outnumber our human cells, although they are small.
Some details are fuzzy, but we know that our microbiomes are linked to our health. The immune system doesn't develop properly without signals from skin microbes. Microbes can influence obesity and have been linked to various inflammatory and autoimmune disorders like rheumatoid arthritis. Our health is connected with the health of our tiny passengers, but scientists are still struggling to understand what a "healthy" microbiome should look like.
We know, for example, that people whose gut ecosystems are overrun by deadly Clostridium difficile can be cured with microbes from a healthy donor - the now-famous fecal transplant. We know probiotics can prevent a horrific infection called NEC (Necrotizing enterocolitis) that kills preemies. Beyond that, results are mostly inconclusive. Probiotics protect against diarrhea in some trials but not others, for example.
While microbes seem important in ascertaining health, understanding the mode of action and mechanisms is unclear. It has been shown that food plays an essential role in setting up the microbiome in the gut, but how the change in diet will alter the microbiome and how it will influence health is an important area yet to be explored.
When our food reaches the microbes in our large intestine, the starch, sugar, fats, and proteins are digested and absorbed. This process leaves a handful of nutrients called "prebiotics." They include a variety of carbohydrates that our enzymes can't digest, including soluble fiber, resistant starch, and specific oligosaccharides. Likely, many of the beneficial effects of fiber and a diet rich in fruits and vegetables may be because of such a diet's effects on gut microbes.
There's no doubt that people will dope via microbes. Companies are talking about significant cosmetic changes. There will be new smells and new functions. It's an exciting area because you don't have to modify a person's genes to give them a new role. You can provide them with a pill with a microbe that has a unique function. If the microbes don't stay around, you might have to take that pill every day, but you could still add a living, bio-producing organism into your system that could last longer or do different things than a typical drug.
The central question of my research group is, how does microbiota maintain homeostasis to define health? By perturbing a typical microbial environment, we would like to know (a) how is the restoration dynamics, (b) how the perturbation affects physiology (e.g., metabolism and innate mucosal immunity), (c) how do gut-adipose-brain axis regulate the gut microbiome or how is physiology being regulated by the microbiome.
We use immunologically (Th1- and Th2) differently biased mice models. We have initiated human studies to compare metabolic and neuronal diseases with gut microbial dynamics. We have also developed mouse intestinal epithelial organoid systems. We plan to extend the work to establish a) adipose organoids to understand the browning of white adipose tissue b) a combination organoid system of Mouse Intestinal Organoid (MIO), Enteric Nervous System (ENS) cellular components, and Vagal Sensory Neurons. Eventually, we will plan to perform organoid studies with human systems.
More focused information on specific research topics that are ongoing in AichLab
Microbes, diet, and them: You are what you eat is a common anecdote. Thus, diet is important in modulating gut microbiomes. To understand the impact of diet-induced microbial dysbiosis on host physiology, we used two strains of conventionally immune-biased mice in our study. We treated young adult (6-8-week-old), male C57BL/6 (Th1 biased) and BALB/c (Th2 biased) mice with diets rich in either non-resistant starch or unsaturated fat or saturated fat for four or eight weeks, along with strain and time-matched controls. Results revealed the differential impact of the diets on intestinal microbes and metabolic parameters like host adiposity, glycemic index, and meta-inflammatory status. We found the starch-rich diet could revert pathogenicity associated with the metabolic parameters after eight weeks in both mice strains. We correlated this alleviation in pathogenicity to the enhancement in a) microbial diversity and b) the abundance in the phyla Verrucomicrobia following eight weeks of dietary intervention. We observed opposite trends in fat-rich diet-treated mice where the diet-induced pathogenicity could be corroborated with abundance in microbial phyla Proteobacteria and Epsilonbacteraeota, coupled with a reduction in Bacteroidetes. The extent of both the physiological changes and microbial influences were specific to mouse strain and duration of treatment. Following these observations in vivo, we conducted in vitro studies to understand the direct interactions between adipose tissue microenvironment resident cell types. Further, we treated matured adipocytes with select microbes to evaluate their anti-adipogenic potential. This study was initiated by Dr. Raktim Mukherjee a PhD candidate in AichLab. A few titbits can be found here.
Gut microbial dysbiosis & consequences: One major role of the microbiome is to maintain health. Thus, dysbiosis disrupts the home to cause diseases. It is, therefore, important to have a balance of beneficial microbes to avoid disruption to happen. But the question is, how do the microbes do it? A key paradigm is to perturb the microbiome and study to establish the role of the microbiome (collection of all commensal microbes, such as bacteria, fungi, viruses, and their genes) in maintaining health. In this project, we used Dextran sulfate sodium (DSS) to perturb the gut microbiota in Th1 and Th2 biased mice.
Results from the current study so far revealed that the dysbiotic condition was stable and long and had a large impact on immune dysregulation following treatment with DSS. Moreover, the DSS-treated group of both mice strains showed typical diseased symptoms resembling human colitis pathophysiology. The current study with DSS treatment also helped us establish a new model system for studying colitis. We utilized a multi-omics approach to understand colitis's onset and etiology in the current study. Further studies are ongoing to understand the mechanism. This study was initiated by Ms. Sohini Mukhopadhyay, a Ph.D. candidate in AichLab. A few relevant publications from this research can be found here.
Altered Light-dark cycle: The light and darkness affect physiology in various ways. The circadian clock is one such vital parameter. The circadian clock can coordinate, regulate, and predict physiology and behavior in response to the standard light-dark (LD) cycle. If we alter the LD cycle, it can perturb behavior, the brain, and associated physiological parameters and the commensal microbiome. The extreme alteration of LD can be done by exposing ethically approved animal models (in this case, mice) in constant darkness (DD) or light. We studied the role of DD for an extended period on male and female mice of Th1 (C57BL/6) and Th2(BALB/c) biased mice. The length of DD exposure and the sex of experimental animals are crucial variables that could alter the impact of DD on the brain, behavior, and physiology, which have not yet been explored. We exposed mice to DD for three and five weeks and studied their impact on 1) behavior, 2) hormones, 3) the prefrontal cortex, and 4) metabolites in male and female mice. We also studied the effect of three weeks of standard light-dark cycle restoration after five weeks of DD on the above-mentioned parameters. The results revealed DD exposure was associated with anxiety-like behavior, increased corticosterone, pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), downregulated neurotrophins (BDNF and NGF), and altered metabolite profile during DD exposure is dependent on the sex of the animals and immunological bias. Females showed a more robust adaptation than males under DD exposure. The work was primarily developed by another PhD candidate Mr. Dhyanendra Singh. More detailed reports can be found here.
Longitudinal analysis of gut microbial and immune development: Gut microbial profile is a dynamic phenomenon. The composition (abundance and diversity) changes spatially and temporally during development and growth. While the consequence of the dynamicity is imaginable and reprehensible, but to be grasped yet confidently. The Aich lab tries to understand the longitudinal dynamic behavior of gut microbiota in neonatal till pre-pubescent (post-natal day 1 till day 28) C57BL/6 mice. Preliminary results established a significant shift in gut microbial structural and functional composition from postnatal day 14 onwards. The gut microbial shift also established a robust age-dependent association with the intestinal mucosal barrier formation postnatal day 14 ahead. Studies further showed a postnatal age-related impact of gut microbiota perturbation, with a gradual increase in the relative abundance of Proteobacteria and a reduction in Bacteroidetes and Firmicutes. We found significant barrier integrity disruption, reduced TJPs and IECs marker expression, and increased systemic inflammation at P14D of AVNM-treated mice. Moreover, the microbiota transplantation showed recolonization of Verrucomicrobia, proving a causal role in barrier functions. Our investigation revealed P14D as a critical period for neonatal intestinal development, regulated by specific microbiota composition. We continue the study with the gut epithelium organoid model developed in AichLab by Mr. Uday Pandey (a graduate student). A master's student Ms. Srishti Shah is now involved in the project. Some relevant information can be found here and on social media.
Direct and indirect assault: While working on various perturbation and developmental models, we also thought to develop a comparative analysis following direct and indirect perturbation of gut microbiome. We already discussed briefly DSS-induced perturbation developed by Sohini. Dr. Pratikshya Ray, a former Ph.D. candidate of the lab, studied the role of various antibiotics (Vancomycin, Ampicillin, Neomycin, Ciprofloxacin, AVNM) on gut microbial dysbiosis and its effects on host physiology. Ms. Swati Sagarika Panda (another Ph.D. candidate) is studying the role of a much broader antibiotic cocktail (we call it a 9-antibiotic cocktail or, in short, 9-AB) on host physiology following a gut microbial perturbation in mice models. Preliminary studies suggested a key impact on the brain and adipogenesis. This adipogenesis is being further studied by master's students, Ms. Shivani Meena, Ms. Isha Dwivedi, and Ms. Akanskshya Nayak, in vitro in 2D- and 3D adipocytes. A comparative direct and indirect assault (perturbation) of the gut microbiome is being studied by Sohini and an MSc student Debopriya Saha.
Microbes, Mitochondria, and their roles in NAFLD and PD: A new venture initiated by the trinity of new Ph.D. candidates Arka Jyoti De, Tanuja Mohanty, and Ankita Das. Ankita also plans to develop a few brain organoids and some integrated MSc project students.
An association study pan omics is being pursued by another iMSc project student Sunaina.
Pre-NISER research
Ph.D. (Supervisor: Professor Dipak Dasgupta). I explored mechanisms of interactions of select antitumor antibiotics with DNA and the role of magnesium ions.
I moved to Stockholm, Sweden [Stockholm University (SU) and Karolinska Institutet] (KI), following the submission of my Ph.D. thesis, to start my 1st PDF Research (Supervisor: Professor Astrid Gräslund, SU) career. My study area aimed to understand higher-ordered DNA structures (by 2D NMR, CD, and other biophysical techniques). Around the same time, I also got introduced to the area of Fluorescence Correlation Spectroscopy (FCS) to understand base pair dynamics in nucleic acids, including PNA, at a single-molecule level with Professor Rudolf Rigler (Rulle, KI). We built the world's first FCS to work in the ultraviolet light region. In Rulle's lab, I also got trained in fixing and maintaining an Argon ion laser and a dye laser.
I decided to move to the University of Saskatchewan (Saskatoon, SK, Canada) for the 2nd PDF position. I preferred the Canadian PDF over other opportunities at Louis Pasteur Institute (Strasbourg, France) or the USA. At Saskatoon [University of Saskatchewan] for my PDF (Supervisor: Professor Jeremy Lee) research, I started working on establishing a higher-ordered DNA structure in vivo using c-myc and c-src oncogenes.
While working on the project, we discovered a novel form of DNA that could conduct electricity when doped with specific transition metal ions. We term this form of DNA as M-DNA [M-stands for 'metal'], and we patented it. We also tried to develop an abzyme against M-DNA. A company named ADNAVANCE was founded. I got so hooked up with the discovery of M-DNA that I declined offers from the Dana Farber Cancer Institute (Harvard University, Boston). I also turned down a job offer from a start-up photonics company in Boston.
I joined a biopharmaceutical company in Canada after my PDF training as a Group Leader [Bio-imaging]. After a year, I accepted a position at the University of Saskatchewan, as in charge of the Biophysical section of Saskatchewan Structural Sciences Center, Saskatoon, SK, Canada. Shortly, I was offered a position at VIDO (now VIDO-Intervac) as a scientist (PI at the level of Assistant Professor) to work in Omics to understand innate mucosal immunity. At VIDO, I developed several programs in innate mucosal immunity to understand the effects of psychological stress on host-pathogen interactions for bovine enteric and respiratory diseases in cattle models and enhance the efficacy of immune stimulators using immune stimulators nanotechnology in chicken.
I continued at VIDO from 2002 to 2009. In 2006, I got promoted to the next level, i.e., equivalent to Associate Professor. During this time, I got associated with a) the Department of Biochemistry and b) the Department of Physiology and Anatomy of the University of Saskatchewan, Saskatoon, Canada, as an Adjunct Professor and Associate faculty member. As an Adjunct professor or associate faculty member, I designed courses on Systems Biology and Physiological Genomics to teach 4th-year undergraduate students.
In 2009, we returned to India. When I left VIDO, I had seven ongoing projects funded by various Canadian Funding Agencies. I could not bring these funds, for obvious reasons, to India. I then transferred those projects to other faculty members of VIDO.
In 2009, I joined NISER as an Associate Professor and started understanding the effects of psychological stress on humans to develop programs on innate mucosal immunity
At NISER:
Systems Biology (BE1), Biophysics & Biostatistics (B203),
Science of Life (I & II) (B101 & 102)
Quantitative & Systems Biology (B558/B758, the course was planned and designed by me) and laboratory courses
Chemical Biology (B457/B657, the course was planned and designed by me)
At UofS
Basic Techniques in Life Science
Bioinformatics
Physiological Genomics
Systems Biology
At Karolinska Institutet
Fluorescence Correlation Spectroscopy (FCS)
Currently the Dean (Research & Development)
Besides my regular academic (teaching and research) activities, I executed various administrative responsibilities as follows
4. Second Chairman
