Doctor of Philosophy, Jamia Hamdard (2016)
Bachelor of Science, University Of Lucknow (2006)
Master of Science, University Of Lucknow (2007)
OBJECTIVE: Chronic pancreatitis (CP) is an inflammatory disease with progressive fibrosis leading to exocrine and endocrine dysfunction. Currently, there are no approved effective therapies for CP. Stimulator of interferon genes (STING) signalling is a key innate immune sensor of DNA. In this study, we evaluated the role of STING signalling in CP.DESIGN: We used an experimental model of CP to test the effect of STING signalling in STING wild-type and knockout mice as well as bone marrow chimaeras (BMCs). STING was activated using a pharmacological agent. Since we found changes in Th17 cells, we used neutralising and control antibodies to determine the role of IL-17A. The effect of STING signalling was further explored in IL-17A generation and we examined the effect of IL-17A on pancreatic stellate cells (PSCs). Human pancreas from patients with CP and without CP were also stained for IL-17A.RESULTS: STING activation decreased CP-associated pancreatic inflammation and fibrosis, whereas absence of STING led to worsening of the disease. BMCs showed that leucocytes play an important role in STING signalling-mediated amelioration of experimental CP. STING deletion was associated with increased Th17 cell infiltration in the pancreas, whereas STING agonist limited this Th17 response. Importantly, anti-IL-17A antibody treatment mitigated the severity of CP in the absence of STING signalling. STING deficiency promoted Th17 polarisation and PSCs express functional IL-17 receptor by upregulating fibrosis genes. Compared with tumour margins, pancreas from patients with CP had significant increase in IL-17A+ cells.CONCLUSION: Unlike acute pancreatitis, STING activation is protective in CP. STING signalling is important in regulating adaptive immune responses by diminishing generation of IL-17A during CP and presents a novel therapeutic target for CP.
View details for PubMedID 30705050
Eosinophilic pancreatitis (EP) is reported in humans; however, the etiology and role of eosinophils in EP pathogenesis are poorly understood and not well explored. Therefore, it is interesting to examine the role of eosinophils in the initiation and progression of pancreatitis pathogenesis. Accordingly, we performed anti-major basic protein immunostaining, chloroacetate esterase, and Masson's trichrome analyses to detect eosinophils, mast cells, and collagen in the tissue sections of mouse and human pancreas. Induced eosinophils accumulation and degranulation were observed in the tissue sections of human pancreatitis, compared with no eosinophils in the normal pancreatic tissue sections. Similarly, we observed induced tissue eosinophilia along with mast cells and acinar cells atrophy in cerulein-induced mouse model of chronic pancreatitis. Additionally, qPCR and ELISA analyses detected induced transcript and protein levels of proinflammatory and profibrotic cytokines, chemokines like IL 5, IL-18, eotaxin-1, eotaxin-2, TGF-?1, collagen-1, collagen-3, fibronectin, and ?-SMA in experimental pancreatitis. Mechanistically, we show that eosinophil-deficient GATA1 and endogenous IL-5-deficient mice were protected from the induction of proinflammatory and profibrotic cytokines, chemokines, tissue eosinophilia, and mast cells in a cerulein-induced murine model of pancreatitis. These human and experimental data indicate that eosinophil accumulation and degranulation may have a critical role in promoting pancreatitis pathogenesis including fibrosis. Taken together, eosinophil tissue accumulation needs appropriate attention to understand and restrict the progression of pancreatitis pathogenesis in humans. NEW & NOTEWORTHY The present study for the first time shows that eosinophils accumulate in the pancreas and promote disease pathogenesis, including fibrosis in earlier reported cerulein-induced experimental models of pancreatitis. Importantly, we show that GATA-1 and IL-5 deficiency protects mice form the induction of eosinophil active chemokines, and profibrotic cytokines, including accumulation of tissue collagen in an experimental model of pancreatitis. Additionally, we state that cerulein-induced chronic pancreatitis is independent of blood eosinophilia.
View details for DOI 10.1152/ajpgi.00210.2017
View details for Web of Science ID 000425923800007
View details for PubMedID 28935682
View details for PubMedCentralID PMC5866419
Pancreatitis is an inflammatory disease characterized by the induction of several pro-inflammatory cytokines like interleukin (IL)-6, IL-8, IL-1?, and IL-1. Recently, a multifunctional innate cytokine IL-15 has been implicated in the protection of several diseases including cancer. Tissue fibrosis is one of the major problems to treat successfully chronic pancreatitis pathogenesis. Therefore, we tested the hypothesis that rIL-15 treatment may induce innate tissue responses and its over-expression will improve the pathogenesis of cerulein-induced chronic pancreatitis, associated remodeling and fibrosis. We observed atrophy of acinar cells, increased inflammation, and increased deposition of perivascular collagen, the up-regulated protein level of TGF-?1, ?-SMA, and collagen-1 in cerulein-induced chronic pancreatitis in mice. Further, we reported that rIL-15 treatment protects mice from the cerulein-induced chronic pancreatitis pathogenesis including acinar cells atrophy, and perivascular accumulation of tissue collagen followed by down-regulation of pro-fibrotic genes such as TGF-?1, ?-SMA, Collagen-1, Collagen-3, and Fibronectin in cerulein-induced chronic pancreatitis in mice. Mechanistically, we show that IL-15-mediated increase of IFN-? responsive iNKT cells in the blood and tissue protects cerulein-induced pancreatic pathogenesis in mice. Of note, a reduced iNKT cells were also observed in the human chronic pancreatitis compared to the normal individuals. Taken together, these data suggest that IL-15 treatment may be a novel therapeutic strategy for treating chronic pancreatitis pathogenesis.
View details for DOI 10.1152/ajpgi.00139.2018
View details for PubMedID 30212254
Several reports indicate that eosinophils are induced in chronic pancreatitis including patients with pancreatic malignancy. However, significance of eosinophilic pancreatitis (EP) is poorly understood and unexplored.Accumulation and degranulation of eosinophils promote pancreatic fibrosis and malignancy.Human pancreatic tissue biopsy samples including chronic pancreatitis (n=3), malignant (n=4), non-malignant (n=3), and normal (n=3) were used for H&E, anti-MBP staining, anti-tryptase staining, anti-IgE staining and Mason's trichrome staining.We show induced eosinophils and degranulated eosinophils indicated by the presence of anti-MBP stained extracellular granules in the malignant pancreatic (pancreatic cancer) and non-malignant human pancreatic tissues. A comparable number of eosinophils were observed in non-malignant and malignant pancreatic tissue sections, but the sections differed in degranulated eosinophils and the presence of extracellular granules. Additionally, induced mast cells and tissue-specific IgE positive cells were also detected in the tissue sections of malignant pancreatitis patients compared to non-malignant human pancreatic patients. Tissue-specific IgE induction is critical for the degranulation of eosinophils and mast cells that may lead to increased accumulation of collagen in malignant compared to non-malignant human pancreatic tissue samples. We show a large number of anti-tryptase stained extracellular granules in the tissue sections of malignant pancreatic cancer patients. Both IgE and eosinophil major basic proteins (MBP) are reported for the activation and degranulation of mast cells in tissues.Taken together, our investigation concludes that eosinophils and mast cells accumulation and degranulation are critical in promoting pancreatitis pathogenesis that may lead to the development of pancreatic fibrosis and malignancy.
View details for DOI 10.15226/2374-815X/5/1/001109
View details for PubMedID 29756031
View details for PubMedCentralID PMC5945222
Airway obstruction is a physiologic feature of asthma, and IL-15 might have an important role in asthma pathogenesis.We tested the hypothesis that regulation of IL-15 is critical for preservation of allergen-induced airway hyperresponsiveness (AHR), airway resistance, and compliance in response to methacholine.Airway inflammation, AHR, resistance, and compliance were assessed in Il15 gene-deficient mice and IL-15-overexpressing mice in an allergen-induced murine model of asthma. We assessed eosinophil numbers by using anti-major basic protein immunostaining, goblet cell hyperplasia by using periodic acid-Schiff staining, and cytokine and chemokine levels by performing quantitative PCR and ELISA.We made a novel observation that IL-15 deficiency promotes baseline airway resistance in naive mice. Moreover, rIL-15 delivery to the lung downregulates expression of proinflammatory cytokines and improves allergen-induced AHR, airway resistance, and compliance. These observations were further validated in doxycycline-inducible CC10-IL-15 bitransgenic mice. Doxycycline-exposed, Aspergillus species extract-challenged CC10-IL-15 bitransgenic mice exhibited significantly reduced levels of proinflammatory cytokines (IL-4, IL-5, and IL-13) and decreased goblet cell hyperplasia. Airway obstruction, including AHR and airway resistance, was diminished in allergen-challenged doxycycline-exposed compared with non-doxycycline-exposed CC10-IL-15 bitransgenic mice. Mechanistically, we observed that IL-15-mediated protection of airway obstruction is associated with induced IFN-?- and IL-10-producing regulatory CD4+CD25+ forkhead box p3 (Foxp3)+ T cells. Additionally, we found that a human IL-15 agonist (ALT-803) improved airway resistance and compliance in an experimental asthma model.We report our novel finding that IL-15 has a potent inhibitory effect on the airway obstruction that occurs in response to environmental allergens.
View details for DOI 10.1016/j.jaci.2017.05.025
View details for Web of Science ID 000426974800011
View details for PubMedID 28606589
View details for PubMedCentralID PMC5723242
Interleukin (IL)-15 overexpression in eosinophilic gastrointestinal disorders is reported, but IL-15's role in promoting eosinophilic gastroenteritis is largely unknown. Therefore, we generated enterocyte-overexpressed IL-15 transgenic mice using Fabpi promoter. The Fabpi-IL-15 (iIL-15) transgenic mice showed induced IL-15 levels in the jejunum with a marked increase in jejunum eosinophils. However, no induction of eosinophilia in the blood or any other gastrointestinal segment was observed. Eosinophilia in the jejunum villus was substantially higher in iIL-15 mice compared to wild-type mice. In addition, goblet cell hyperplasia was also observed in the jejunum of iIL-15 mice. Furthermore, a significant correlation between induced IL-15 transcript and the IL-18 transcripts was observed. Therefore, to further understand the role of IL-18 in IL-15 mice associated gastrointestinal disorders, we generated iIL-15/IL-18R?-/- mice. Using these mice, we found that IL-18 has an important role in promoting IL-15-induced eosinophilia. As intestinal IL-15 overexpression is reported in food intolerance, we examined OVA intolerance in iIL-15 mice. The OVA-sensitized and challenged iIL-15 mice experienced weight loss, diarrhea and eosinophilia in the jejunum. Taken together, our findings demonstrate that intestinal IL-15 overexpression induces IL-18-dependent eosinophilia and immunoglobulins in the intestine that promotes food allergic responses.
View details for DOI 10.1111/imcb.1036
View details for Web of Science ID 000428212100005
View details for PubMedID 29363170
View details for PubMedCentralID PMC5866184
Food allergy, a commonly increasing problem worldwide, defined as an adverse immune response to food. A variety of immune-related effector cells such as mast cells, eosinophils, neutrophils, and T cells are involved in food-related allergic responses categorized as IgE mediated, non-IgE mediated, and mixed (IgE and non-IgE) depending upon underlying immunological mechanisms. The dietary antigens mainly target the gastrointestinal tract including pancreas that gets inflamed due to food allergy and leads acute pancreatitis. Reports indicate several food proteins induce pancreatitis; however, detailed underlying mechanism of food-induced pancreatitis is unexplored. The aim of the review is to understand and update the current scenario of food-induced pancreatitis. A comprehensive literature search of relevant research articles has been performed through PubMed, and articles were chosen based on their relevance to food allergen-mediated pancreatitis. Several cases in the literature indicate that acute pancreatitis has been provoked after the consumption of mustard, milk, egg, banana, fish, and kiwi fruits. Food-induced pancreatitis is an ignored and unexplored area of research. The review highlights the significance of food in the development of pancreatitis and draws the attention of physicians and scientists to consider food allergies as a possible cause for initiation of pancreatitis pathogenesis.
View details for DOI 10.1007/s10620-017-4817-2
View details for Web of Science ID 000415996900006
View details for PubMedID 29086330
View details for PubMedCentralID PMC5718054
View details for Web of Science ID 000407750400697
Pancreatitis is inflammation of pancreas and caused by a number of factors including pancreatic duct obstruction, alcoholism, and mutation in the cationic trypsinogen gene. Pancreatitis is represented as acute pancreatitis with acute inflammatory responses and; chronic pancreatitis characterized by marked stroma formation with a high number of infiltrating granulocytes (such as neutrophils, eosinophils), monocytes, macrophages and pancreatic stellate cells (PSCs). These inflammatory cells are known to play a central role in initiating and promoting inflammation including pancreatic fibrosis, i.e., a major risk factor for pancreatic cancer. A number of inflammatory cytokines are known to involve in promoting pancreatic pathogenesis that lead pancreatic fibrosis. Pancreatic fibrosis is a dynamic phenomenon that requires an intricate network of several autocrine and paracrine signaling pathways. In this review, we have provided the details of various cytokines and molecular mechanistic pathways (i.e., Transforming growth factor-?/SMAD, mitogen-activated protein kinases, Rho kinase, Janus kinase/signal transducers and activators, and phosphatidylinositol 3 kinase) that have a critical role in the activation of PSCs to promote chronic pancreatitis and trigger the phenomenon of pancreatic fibrogenesis. In this review of literature, we discuss the involvement of several pro-inflammatory and anti-inflammatory cytokines, such as in interleukin (IL)-1, IL-1?, IL-6, IL-8 IL-10, IL-18, IL-33 and tumor necrosis factor-?, in the pathogenesis of disease. Our review also highlights the significance of several experimental animal models that have an important role in dissecting the mechanistic pathways operating in the development of chronic pancreatitis, including pancreatic fibrosis. Additionally, we provided several intermediary molecules that are involved in major signaling pathways that might provide target molecules for future therapeutic treatment strategies for pancreatic pathogenesis.
View details for DOI 10.4292/wjgpt.v8.i1.10
View details for PubMedID 28217371
View details for PubMedCentralID PMC5292603
Pancreatitis is a condition characterized by parenchymal inflammation of the pancreas, which is often associated with lung injury due to low level of oxygen and the condition is termed as acute pancreatitis-associated lung injury (APALI). Clinical reports indicated that ~ 20% to 50% of patients from low oxygen levels in blood with acute respiratory distress syndrome (ARDS). ARDS is a severe form of acute lung injury (ALI), a pulmonary disease with impaired airflow making patients difficult to breathe. ALI is frequently observed in patients with severe acute pancreatitis. Approximately one third of severe pancreatitis patients develop acute lung injury and acute respiratory distress syndrome that account for 60% of all deaths within the first week. The major causes of ALI and ARDS are sepsis, trauma, aspiration, multiple blood transfusion, and most importantly acute pancreatitis. The molecular mechanisms of ALI and ARDS are still not well explored, but available reports indicate the involvement of several pro-inflammatory mediators including cytokines (TNF-?, IL-1?, IL-6) and chemokines [like interleukin-8 (IL-8) and macrophage inhibitory factor (MIF)], as well as macrophage polarization regulating the migration and pulmonary infiltration of neutrophils into the pulmonary interstitial tissue, causing injury to the pulmonary parenchyma. Acute lung injury and acute respiratory distress syndrome in acute pancreatitis remains an unsolved issue and needs more research and resources to develop effective treatments and therapies. However, recent efforts have tested several molecules in an experimental model and showed promising results as a treatment option. The current review summarized the mechanism that is operational in pancreatitis-associated acute respiratory failure and respiratory distress syndrome in patients and current treatment options.
View details for DOI 10.15406/moji.2017.05.00149
View details for PubMedID 29399623
View details for PubMedCentralID PMC5793936
Compromised receptivity of the endometrium is a major cause of unexplained infertility, implantation failure and subclinical pregnancy loss. In order to investigate the changes in endometrial protein profile as a cause of unexplained infertility, the current study was undertaken to analyze the differentially expressed proteins of endometrium from early-secretory (LH+2) to mid-secretory phase (LH+7), in women with unexplained infertility.2-D gel electrophoresis was performed to analyze the proteomic changes between early- (n?=?8) and mid-secretory (n?=?8) phase endometrium of women with unexplained infertility. The differentially expressed protein spots were identified by LC-MS analysis and validated by immunoblotting and immuno-histochemical analysis in early- (n?=?4) and mid-secretory (n?=?4) phase endometrium of infertile women. Validated proteins were also analyzed in early- (n?=?4) and mid-secretory (n?=?4) phase endometrium of fertile women.Nine proteins were found to be differentially expressed between early- and mid- secretory phases of endometrium of infertile women. The expression of Ras-related protein Rap-1b, Protein disulfide isomerase A3, Apolipoprotein-A1 (Apo-A1), Cofilin-1 and RAN GTP-binding nuclear protein (Ran) were found to be significantly increased, whereas, Tubulin polymerization promoting protein family member 3, Superoxide dismutase [Cu-Zn], Sorcin, and Proteasome subunit alpha type-5 were significantly decreased in mid- secretory phase endometrium of infertile women as compared to early-secretory phase endometrium of infertile women. Validation of 4 proteins viz. Sorcin, Cofilin-1, Apo-A1 and Ran were performed in separate endometrial biopsy samples from infertile women. The up-regulated expression of Sorcin and down-regulated expression of Cofilin-1 and Apolipoprotein-A1, were observed in mid-secretory phase as compared to early-secretory phase in case of fertile women.De-regulation of the expression of Sorcin, Cofilin-1, Apo-A1 and Ran, during early- to mid-secretory phase may have physiological significance and it may be one of the causes for altered differentiation and/or maturation of endometrium, in women with unexplained infertility.
View details for DOI 10.1371/journal.pone.0111687
View details for Web of Science ID 000347121300014
View details for PubMedID 25405865
View details for PubMedCentralID PMC4236019
View details for DOI 10.4172/jpb.1000340
(-)-Epigallocatechin-3-gallate (EGCG), the major polyphenol in green tea, has been shown to inhibit carcinogenesis of various tumor types. The aim of this study was to elucidate the antiproliferative potential of EGCG and its mechanism in human endometrial cancer cells (Ishikawa cells) and primary endometrial adenocarcinoma cells. The antiproliferative effect of EGCG was evaluated by cell viability assay. Apoptosis was measured by annexin/propidium iodide staining. Reactive oxygen species (ROS) generation was measured by using 2',7'-dichlorofluorescin diacetate dye. Expression of mitogen-activated protein kinases, proliferation and apoptotic markers were measured by immunoblot analysis. EGCG was found to inhibit proliferation in Ishikawa as well as in primary endometrial adenocarcinoma cells and effectively down-regulated the expression of proliferation markers, i.e., estrogen receptor ?, progesterone receptor, proliferating cell nuclear antigen and cyclin D1. EGCG also decreased the activation of ERK and downstream transcription factors fos and jun. EGCG caused apoptotic cell death accompanied by up-regulation of proapoptotic Bax and down-regulation of antiapoptotic protein Bcl2. EGCG induced the cleavage of caspase-3 and poly(ADP-ribose) polymerase, the hallmark of apoptosis. EGCG significantly induced the ROS generation as well as p38 activation in Ishikawa cells, which appeared to be a critical mediator in EGCG-induced apoptosis. The apoptotic effect of EGCG and the p38 activation were blocked by pretreatment of cells with the ROS scavenger N-acetylcysteine. EGCG reduced the glutathione levels, which might be responsible for enhanced ROS generation causing oxidative stress in endometrial cancer cells. Taken together, these results suggest that EGCG inhibits cellular proliferation via inhibiting ERK activation and inducing apoptosis via ROS generation and p38 activation in endometrial carcinoma cells.
View details for DOI 10.1016/j.jnutbio.2012.06.013
View details for Web of Science ID 000320096400002
View details for PubMedID 22959059