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1.
J Med Internet Res ; 24(1): e29969, 2022 01 03.
Article in English | MEDLINE | ID: mdl-34982034

ABSTRACT

BACKGROUND: Leveraging artificial intelligence (AI)-driven apps for health education and promotion can help in the accomplishment of several United Nations sustainable development goals. SnehAI, developed by the Population Foundation of India, is the first Hinglish (Hindi + English) AI chatbot, deliberately designed for social and behavioral changes in India. It provides a private, nonjudgmental, and safe space to spur conversations about taboo topics (such as safe sex and family planning) and offers accurate, relatable, and trustworthy information and resources. OBJECTIVE: This study aims to use the Gibson theory of affordances to examine SnehAI and offer scholarly guidance on how AI chatbots can be used to educate adolescents and young adults, promote sexual and reproductive health, and advocate for the health entitlements of women and girls in India. METHODS: We adopted an instrumental case study approach that allowed us to explore SnehAI from the perspectives of technology design, program implementation, and user engagement. We also used a mix of qualitative insights and quantitative analytics data to triangulate our findings. RESULTS: SnehAI demonstrated strong evidence across fifteen functional affordances: accessibility, multimodality, nonlinearity, compellability, queriosity, editability, visibility, interactivity, customizability, trackability, scalability, glocalizability, inclusivity, connectivity, and actionability. SnehAI also effectively engaged its users, especially young men, with 8.2 million messages exchanged across a 5-month period. Almost half of the incoming user messages were texts of deeply personal questions and concerns about sexual and reproductive health, as well as allied topics. Overall, SnehAI successfully presented itself as a trusted friend and mentor; the curated content was both entertaining and educational, and the natural language processing system worked effectively to personalize the chatbot response and optimize user experience. CONCLUSIONS: SnehAI represents an innovative, engaging, and educational intervention that enables vulnerable and hard-to-reach population groups to talk and learn about sensitive and important issues. SnehAI is a powerful testimonial of the vital potential that lies in AI technologies for social good.


Subject(s)
Sexual Health , Text Messaging , Adolescent , Artificial Intelligence , Female , Humans , India , Male , Reproductive Health , Young Adult
2.
Neurosci Lett ; 704: 212-219, 2019 06 21.
Article in English | MEDLINE | ID: mdl-30974231

ABSTRACT

Human Islet Amyloid Polypeptide or amylin is a neuroendocrine peptide with important endocrine and paracrine functions. Excessive production and accumulation of human amylin in the pancreas can lead to its aggregation and apoptosis of islet ß-cells. Amylin has been shown to function within the central nervous system to decrease food intake, and more recently, it has been revealed that amylin is directly transcribed from neurons of the central nervous system, including the hypothalamus, arcuate nucleus, medial preoptic area, and nucleus accumbens. These findings alter the current model of how amylin targets the nervous system, and as a result may lead to obesity and type II diabetes mellitus. Here we set out to use Caenorhabditis elegans as an inducible in vivo model system to study the effects of amylin overexpression in tissues that include the nervous system. We profiled the transcriptional changes in transgenic animals expressing human amylin through RNA-seq. Using this genome-wide approach our results revealed for the first time that expression of human amylin in tissues including the nervous system induce diverse physiological responses in various signaling pathways. From our characterization of transgenic C. elegans animals expressing human amylin, we also observed specific defects in neural developmental programs as well as sensory behavior. Taken together, our data demonstrate the utility of using C. elegans as a valuable in vivo model to study human amylin toxicity.


Subject(s)
Caenorhabditis elegans/metabolism , Islet Amyloid Polypeptide/metabolism , Models, Animal , Animals , Animals, Genetically Modified , Behavior, Animal , Caenorhabditis elegans/embryology , Caenorhabditis elegans/genetics , Caenorhabditis elegans/growth & development , Humans , Islet Amyloid Polypeptide/genetics , Locomotion , Neurons/physiology , Signal Transduction , Transcription, Genetic
3.
Biochim Biophys Acta Biomembr ; 1860(9): 1721-1733, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29627323

ABSTRACT

Misfolded toxic human islet amyloid polypeptide or amylin (hA) and plasma membrane-associated redox complex, NADPH oxidase (NOX), have been implicated in the islet ß-cell demise associated with type-2 diabetes mellitus (T2DM). Studies show that hA accumulation is stressful to ß-cells and that misfolding of human amylin evokes redox stress and activates mitogen activated protein (MAP) kinases, p38 MAPK and c-Jun N-terminal (JNK) kinase. However, the molecular link and causality between hA-evoked redox stress, NOX activity and MAP kinases signaling in pancreatic ß-cells is incompletely understood. Here, we show that in the process of activating JNK, aggregation prone hA also activates an upstream apoptosis signal regulating kinase-1 (ASK1) with concomitant decrease in intracellular levels of reduced glutathione. Inhibition of ASK1 kinase activity, either by specific ASK1 inhibitor, NQDI1 or by thiol antioxidants reduces human amylin-evoked ASK1 and JNK activation and consequently human amylin toxicity in rat insulinoma Rin-m5F cells and human islets. ß-cell specific overexpression of human amylin in mouse islets elicited ASK1 phosphorylation and activation in ß-cells but not in other rodent's islet or exocrine cells. This ASK1 activation strongly correlated with islet amyloidosis and diabetes progression. Cytotoxic human amylin additionally stimulated pro-oxidative activity and expressions of plasma membrane bound NADPH oxidase (NOX) and its regulatory subunits. siRNA mediated NOX1 knockdown and selective NOX inhibitors, ML171 and apocynin, significantly reduced hA-induced mitochondrial stress in insulinoma beta-cells. However, NOX inhibitors were largely ineffective against hA-evoked redox stress and activation of cytotoxic ASK1/JNK signaling complex. Thus, our studies suggest that NOX1 and ASK1 autonomously mediate human amylin-evoked redox and mitochondrial stress in pancreatic ß-cells.

4.
Indian J Med Res ; 148(Suppl): S1-S9, 2018 12.
Article in English | MEDLINE | ID: mdl-30964076

ABSTRACT

Given the magnitude of the family planning programme in India, there is a need to strengthen the coordination of all its aspects, focusing on planning, programmes, monitoring, training and procurement. The quality of care in family planning must be a major focus area to ensure the success of family planning programmes. Despite serious efforts and progress, India has yet to achieve its family planning goals. Furthermore, there is a need for greater male participation both as enablers and beneficiaries and also address the sexual and reproductive needs of the youth. It is imperative for the government to ensure the prioritization of family planning in the national development agenda. Family planning is crucial for the achievement of the sustainable development goals, and subsequent efforts need to be made to improve access and strengthen quality of family planning services.


Subject(s)
Contraception/trends , Family Planning Services/trends , Health Services Needs and Demand , Developing Countries , Female , Health Services Accessibility/trends , Humans , India/epidemiology , Male
5.
Handb Exp Pharmacol ; 245: 271-312, 2018.
Article in English | MEDLINE | ID: mdl-29043504

ABSTRACT

Human islet amyloid polypeptide or amylin (hA) is a 37-amino acid peptide hormone produced and co-secreted with insulin by pancreatic ß-cells. Under physiological conditions, hA regulates a broad range of biological processes including insulin release and slowing of gastric emptying, thereby maintaining glucose homeostasis. However, under the pathological conditions associated with type 2 diabetes mellitus (T2DM), hA undergoes a conformational transition from soluble random coil monomers to alpha-helical oligomers and insoluble ß-sheet amyloid fibrils or amyloid plaques. There is a positive correlation between hA oligomerization/aggregation, hA toxicity, and diabetes progression. Because the homeostatic balance between hA synthesis, release, and uptake is lost in diabetics and hA aggregation is a hallmark of T2DM, this chapter focuses on the biophysical and cell biology studies investigating molecular mechanisms of hA uptake, trafficking, and degradation in pancreatic cells and its relevance to h's toxicity. We will also discuss the regulatory role of endocytosis and proteolytic pathways in clearance of toxic hA species. Finally, we will discuss potential pharmacological approaches for specific targeting of hA trafficking pathways and toxicity in islet ß-cells as potential new avenues toward treatments of T2DM patients.


Subject(s)
Amyloidosis/etiology , Diabetes Mellitus, Type 2/etiology , Islet Amyloid Polypeptide/physiology , Islets of Langerhans/metabolism , Animals , Diabetes Mellitus, Type 2/drug therapy , Endocytosis , Humans , Islet Amyloid Polypeptide/chemistry , Proteasome Endopeptidase Complex/physiology , Protein Aggregates
6.
Biochem J ; 473(17): 2655-70, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27340132

ABSTRACT

Toxic human amylin (hA) oligomers and aggregates are implicated in the pathogenesis of type 2 diabetes mellitus (T2DM). Although recent studies demonstrated a causal connection between hA uptake and toxicity in pancreatic cells, the mechanism of amylin's clearance following its internalization and its relationship to toxicity is yet to be determined, and hence was investigated here. Using pancreatic rat insulinoma ß-cells and human islets as model systems, we show that hA, following its internalization, first accumulates in the cytosol followed by its translocation into nucleus, and to a lesser extent lysosomes, keeping the net cytosolic amylin content low. An increase in hA accumulation in the nucleus of pancreatic cells correlated with its cytotoxicity, suggesting that its excessive accumulation in the nucleus is detrimental. hA interacted with 20S core and 19S lid subunits of the ß-cell proteasomal complex, as suggested by immunoprecipitation and confocal microscopy studies, which subsequently resulted in a decrease in the proteasome's proteolytic activity in these cells. In vitro binding and activity assays confirmed an intrinsic and potent ability of amylin to interact with the 20S core complex thereby modulating its proteolytic activity. Interestingly, less toxic and aggregation incapable rat amylin (rA) showed a comparable inhibitory effect on proteasome activity and protein ubiquitination, decoupling amylin aggregation/ toxicity and amylin-induced protein stress. In agreement with these studies, inhibition of proteasomal proteolytic activity significantly increased intracellular amylin content and toxicity. Taken together, our results suggest a pivotal role of proteasomes in amylin's turnover and detoxification in pancreatic cells.


Subject(s)
Islet Amyloid Polypeptide/metabolism , Pancreas/metabolism , Proteasome Endopeptidase Complex/metabolism , Animals , Cell Line, Tumor , Cell Nucleus/metabolism , Cytoplasm/metabolism , Humans , Islet Amyloid Polypeptide/toxicity , Microscopy, Confocal , Pancreas/cytology , Rats
7.
Adv Exp Med Biol ; 855: 95-116, 2015.
Article in English | MEDLINE | ID: mdl-26149927

ABSTRACT

Amyloidosis is a biological event in which proteins undergo structural transitions from soluble monomers and oligomers to insoluble fibrillar aggregates that are often toxic to cells. Exactly how amyloid proteins, such as the pancreatic hormone amylin, aggregate and kill cells is still unclear. Islet amyloid polypeptide, or amylin, is a recently discovered hormone that is stored and co-released with insulin from pancreatic islet ß-cells. The pathology of type 2 diabetes mellitus (T2DM) is characterized by an excessive extracellular and intracellular accumulation of toxic amylin species, soluble oligomers and insoluble fibrils, in islets, eventually leading to ß-cell loss. Obesity and elevated serum cholesterol levels are additional risk factors implicated in the development of T2DM. Because the homeostatic balance between cholesterol synthesis and uptake is lost in diabetics, and amylin aggregation is a hallmark of T2DM, this chapter focuses on the biophysical and cell biology studies exploring molecular mechanisms by which cholesterol and phospholipids modulate secondary structure, folding and aggregation of human amylin and other amyloid proteins on membranes and in cells. Amylin turnover and toxicity in pancreatic cells and the regulatory role of cholesterol in these processes are also discussed.


Subject(s)
Amyloidosis/physiopathology , Cholesterol/physiology , Islet Amyloid Polypeptide/chemistry , Islets of Langerhans/physiopathology , Phospholipids/physiology , Protein Folding , Amino Acid Sequence , Amyloidosis/etiology , Animals , Diabetes Mellitus, Type 2/physiopathology , Humans , Molecular Sequence Data , Protein Conformation , Sequence Homology, Amino Acid
8.
Phys Chem Chem Phys ; 15(30): 12558-71, 2013 Aug 14.
Article in English | MEDLINE | ID: mdl-23793354

ABSTRACT

Human amylin-derived oligomers and aggregates are believed to play an important role in the pathogenesis of type II diabetes mellitus (T2DM). In addition to amylin-evoked cell attrition, T2DM is often accompanied by elevated serum copper levels. Although previous studies have shown that human amylin, in the course of its aggregation, produces hydrogen peroxide (H2O2) in solution, and that this process is exacerbated in the presence of copper(ii) ions (Cu(2+)), very little is known about the mechanism of interaction between Cu(2+) and amylin in pancreatic ß-cells, including its pathological significance. Hence, in this study we investigated the mechanism by which Cu(2+) and human amylin catalyze formation of reactive oxygen species (ROS) in cells and in vitro, and examined the modulatory effect of Cu(2+) on amylin aggregation and toxicity in pancreatic rat insulinoma (RIN-m5F) ß-cells. Our results indicate that Cu(2+) interacts with human and rat amylin to form metalo-peptide complexes with low aggregative and oxidative properties. Human and non-amyloidogenic rat amylin produced minute (nM) amounts of H2O2, the accumulation of which was slightly enhanced in the presence of Cu(2+). In a marked contrast to human and rat amylin, and in the presence of the reducing agents glutathione and ascorbate, Cu(2+) produced µM concentrations of H2O2 surpassing the amylin effect by several fold. The current study shows that human and rat amylin not only produce but also quench H2O2, and that human but not rat amylin significantly decreases the amount of H2O2 in solution produced by Cu(2+) and glutathione. Similarly, human amylin was found to also decrease hydroxyl radical formation elicited by Cu(2+) and glutathione. Furthermore, Cu(2+) mitigated the toxic effect of human amylin by inhibiting activation of pro-apoptotic caspase-3 and stress-kinase signaling pathways in rat pancreatic insulinoma cells in part by stabilizing human amylin in its native conformational state. This sacrificial quenching of metal-catalyzed ROS by human amylin and copper's anti-aggregative and anti-apoptotic properties suggest a novel and protective role for the copper-amylin complex.


Subject(s)
Copper/chemistry , Islet Amyloid Polypeptide/chemistry , Animals , Apoptosis/drug effects , Cell Line, Tumor , Circular Dichroism , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Glutathione/chemistry , Humans , Hydrogen Peroxide/chemistry , Hydrogen Peroxide/metabolism , Hydrogen Peroxide/toxicity , Hydroxyl Radical/chemistry , Hydroxyl Radical/metabolism , Hydroxyl Radical/toxicity , Ions/chemistry , Islet Amyloid Polypeptide/metabolism , Oxidative Stress/drug effects , Rats
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