Zeenat Mirza

Conotoxins: Structure, Therapeutic Potential and Pharmacological Applications

Cone snails, also known as marine gastropods, from Conus genus produce in their venom a diverse range of small pharmacologically active structured peptides called conotoxins. The cone snail venoms are widely unexplored arsenal of toxins with therapeutic and pharmacological potential, making them a treasure trove of ligands and peptidic drug leads. Conotoxins are small disulfide bonded peptides, which act as remarkable selective inhibitors and modulators of ion channels (calcium, sodium, potassium), nicotinic acetylcholine receptors, noradrenaline transporters, N-methyl-D-aspartate receptors, and neurotensin receptors. They are highly potent and specific against several neuronal targets making them valuable as research tools, drug leads and even therapeutics. In this review, we discuss their gene superfamily classification, nomenclature, post-translational modification, structural framework, pharmacology and medical applications of the active conopeptides. We aim to give an overview of their structure and therapeutic potential. Understanding these aspects of conopeptides will help in designing more specific peptidic analogues.

Proteomics Approaches to Understand Linkage Between Alzheimer’s Disease and Type 2 Diabetes Mellitus

Alzheimers disease (AD) is a progressive neurological disease of the brain leading to the irreversible loss of neurons and intellectual abilities. Diabetes mellitus type 2 (T2DM) is a metabolic disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency. The prevalence of AD and T2DM is increasing at an alarming rate and has become a major public health concern worldwide. The clinico-pathological relationship between AD and T2DM has been debated for more than a decade. Recent epidemiological studies have provided direct evidence that T2DM is a strong risk factor for AD and numerous studies have demonstrated that patients with diabetes have an increased risk of developing AD as compared with healthy individuals. The underlying biological mechanisms that link the development of diabetes with AD are not fully understood and therefore are worth intensive research. The existence of proteomic links between AD and diabetes is an important topic currently under active debate. An understanding of the complex association between diabetes and AD is necessary for the development of novel drug therapies and lifestyle guidelines aimed at the treatment and/or prevention of these diseases. This review aims to summarize what is currently known about the biological and especially proteomic relationships and similarities between these two age-related devastating diseases of modern day life. This study may also aid in future for the identification of a single or a panel of potential blood-based protein biomarkers for early diagnosis of AD and T2DM with high sensitivity and specificity.

An Association of Virus Infection with Type 2 Diabetes and Alzheimer’s Disease

Diabetes mellitus type 2 is a metabolic disorder characterized by high blood glucose due to insulin deficiency or resistance. Alzheimers disease (AD) is a complex neurodegenerative disease leading to irreversible loss of neurons, intellectual abilities, memory and reasoning. The worldwide prevalence of diabetes and AD in elderly population is a major public health concern. Interestingly, both health issues are unraveling the puzzling links. The clinico-pathological relationship between diabetes and AD has been reported at genomic and proteomic levels. The association of virus infection in type 2 diabetes mellitus and AD has been reported in few recent studies, some have shown direct evidence of virus infection in diabetes and AD while other have shown that diabetes increases the risk of developing AD. This review aims to summarize the association of few common viruses like Hepatitis C Virus and Herpes Simplex Virus-1 which affects both these two age-related devastating diseases. We also discuss the pathological links of Influenza virus, Cytomegalovirus, West Nile virus, Enterovirus, Herpes Simplex Virus-2, Hepatitis viruses in diabetes and Influenza virus, Picornavirus and Borna disease virus in AD. Establishing such relationships and defining their common pathogenesis and patho-physiological mechanisms may lead to new concepts and paths for developing novel preventive strategies and pharmacological treatment options for diabetes and AD. This study may aid in future for the identification of a single or a panel of likely blood-based viral biomarkers for early diagnosis of diabetes and AD with high sensitivity and specificity.

The role of viruses in neurodegenerative and neurobehavioral diseases.

Neurodegenerative and neurobehavioral diseases may be caused by chronic and neuropathic viral infections and may result in a loss of neurons and axons in the central nervous system that increases with age. To date, there is evidence of systemic viral infections that occur with some neurodegenerative conditions such as Alzheimers disease, Parkinsons disease, amyotrophic lateral sclerosis, multiple sclerosis, autism spectrum disorders, and HIV-associated neurocognitive disorders. With increasing lifespan, the incidence of neurodegenerative diseases increases consistently. Neurodegenerative diseases affect approximately 37 million people worldwide and are an important cause of mortality. In addition to established non-viral-induced reasons for neurodegenerative diseases, neuropathic infections and viruses associated with neurodegenerative diseases have been proposed. Neuronal degeneration can be either directly or indirectly affected by viral infection. Viruses that attack the human immune system can also affect the nervous system and interfere with classical pathways of neurodegenerative diseases. Viruses can enter the central nervous system, but the exact mechanism cannot be understood well. Various studies have supported viral- and non-viral-mediated neurodegeneration at the cellular, molecular, genomic and proteomic levels. The main focus of this review is to illustrate the association between viral infections and both neurodegenerative and neurobehavioral diseases, so that the possible mechanism and pathway of neurodegenerative diseases can be better explained. This information will strengthen new concepts and ideas for neurodegenerative and neurobehavioral disease treatment.

Transcriptomics Study of Neurodegenerative Disease: Emphasis on Synaptic Dysfunction Mechanism in Alzheimer's Disease

Alzheimers disease (AD) is a common neurodegenerative disorder primarily affecting memory and thinking ability; caused by progressive degeneration and death of nerve cells. In this study, we integrated multiple dataset retrieved from the National Center for Biotechnology Informations Gene Expression Omnibus database, and took a systems-biology approach to compare and distinguish the molecular network based synaptic dysregulation associated with AD in particular and neurodegenerative diseases in general. We first identified 832 differentially expressed genes using cut off P value <0.5 and fold change > 2, followed by gene ontology study to identify genes associated with synapse (n=95) [membrane associated guanylate kinase, 2, amyloid beta precursor protein, neurotrophic tyrosine kinase, receptor, type 2], synapse part [γ-aminobutyric acid A receptor, γ1], synaptic vesicle [glutamate receptor, ionotropic, α-amino-3-hydroxy-5- methyl-4-isoxazole propionic acid receptor 2, synaptoporin], pre- and post-synaptic density [neuronal calcium sensor 1, glutamate receptor, metabotropic 3]. We integrated these data with known pathways using Ingenuity Pathway Analysis tool and found following synapse associated pathways to be most affected; γ-aminobutyric acid receptor signaling, synaptic long term potentiation/depression, nuclear factor-erythroid 2-related factor 2-mediated oxidative stress response, huntingtons disease signaling and Reelin signaling in neurons. In conclusion, synaptic dysfunction is tightly associated with the development and progression of neurodegenerative diseases like AD.

Low expression of leptin and its association with breast cancer: A transcriptomic study.

The incidence of breast cancer is alarmingly increasing worldwide and also among Saudi women. Obesity is linked with an increased cancer risk and studies have also revealed that leptin may be involved in breast tumorigenesis particularly among obese women. Numerous transcriptomic studies have been carried out worldwide; however, molecular studies among breast cancer patients of diverse ethnic groups from the Arabian Peninsula are scarce. In the present study, whole transcriptome analysis of 45 surgically resected breast tumors from Saudi Arabian female patients was carried out. Expression data were analyzed, and molecular networks and canonical pathways were identified. We identified 1,159 differentially expressed genes using p-value with a false discovery rate <0.05 and a fold-change >2 as a cut-off. Using ingenuity pathway analysis tool, we identified many canonical pathways that were implicated in breast cancer for the first time. Notably, along with other lipid metabolism molecules, leptin (LEP) was one of the most downregulated genes (fold cut-off, −7.03) with significant differences between the breast cancer and the control groups (p<0.0001) and was further confirmed in all the samples using qPCR. Transcriptomic profiling of breast cancer from a Saudi female population revealed downregulation of LEP. Molecular pathway analysis demonstrated the role of LEP and other associated molecules of the lipid metabolism pathway. Involvement of leptin and lipid metabolism in breast cancer was highlighted. The majority of cases presented were of late stage, stressing the need to educate individuals concerning early diagnostic testing and the life-style risk factors for breast cancer such as unhealthy diet and obesity.

Application of Proteomic Tools in Modern Nanotechnological Approaches Towards Effective Management of Neurodegenerative Disorders

Neurodegeneration is the progressive loss of structure or function of neurons leading to neuronal death, usually associated with ageing. Some of the common neurodegenerative disorders include Alzheimers disease, Parkinsons disease, Creutzfeldt-Jakob disease, and Huntingtons disease. Due to recent advancements in highthroughput technologies in various disciplines such as genomics, epigenomics, metabolomics and proteomics, there has been a great demand for detection of specific macromolecules such as hormones, drug residues, miRNA, DNA, antibodies, peptides, proteins, pathogens and xenobiotics at nano-level concentrations for in-depth understanding of disease mechanisms as well as for the development of new therapeutic strategies. The present review focuses on the management of agerelated neurodegenerative disorders using proteomics and nanotechnological approaches. In addition, this review also highlights the metabolism and disposition of nano-drugs and nano-enabled drug delivery in neurodegenerative disorders.

Panacea seed “Nigella”: A review focusing on regenerative effects for gastric ailments

Nigella sativa (NS) or black cumin is a dark, thin, and crescent-shaped, seeded shrub belonging to the Ranunculaceae family commonly growing on Mediterranean coasts in Saudi Arabia, northern Africa and Asia. They have amazing curative and therapeutic features that make them one of the most popular, safe, non-detrimental, and cytoprotective medicinal plant that can be used for prevention and treatment of many complicated diseases. Originally, N. sativa was used to treat migraines and allergy, and researches have shown its effectiveness in destroying cancer cells as well. The gastro protective effect of NS oil and its constituents has also been reported earlier; however, the complete perception on etiology and pathogenesis of gastric ulcer is not yet clear. Herein, we attempt to unveil some of the potential mechanisms exhibited by NS in preventing problems related to gastric ulcers. Gastric ailments like ulcers and tumors are the most common disorders of the gastro-intestinal tract in the present day life of the industrialized world. Gastric ulcer being a multifaceted problem exhibits complex etiology and is the fourth most common cause of cancer mortality. Drug interactions and toxicity are the main hindrances in chemotherapy. The existing merits and demerits of modern-day drugs make us turn toward the plant kingdom which may provide a valuable resource of novel potent natural compounds for pharmaceuticals or alternately, as dietary supplements. In this context, the revered phytotherapeutic N. sativa comes as a promising savior in today’s times. This review aims to summarize, both the functional and disease-related effects in the area of gastroenterology.

Assessment of Radiation Induced Therapeutic Effect and Cytotoxicity in Cancer Patients Based on Transcriptomic Profiling

Toxicity induced by radiation therapy is a curse for cancer patients undergoing treatment. It is imperative to understand and define an ideal condition where the positive effects notably outweigh the negative. We used a microarray meta-analysis approach to measure global gene-expression before and after radiation exposure. Bioinformatic tools were used for pathways, network, gene ontology and toxicity related studies. We found 429 differentially expressed genes at fold change >2 and p-value <0.05. The most significantly upregulated genes were synuclein alpha (SNCA), carbonic anhydrase I (CA1), X-linked Kx blood group (XK), glycophorin A and B (GYPA and GYPB), and hemogen (HEMGN), while downregulated ones were membrane-spanning 4-domains, subfamily A member 1 (MS4A1), immunoglobulin heavy constant mu (IGHM), chemokine (C-C motif) receptor 7 (CCR7), BTB and CNC homology 1 transcription factor 2 (BACH2), and B-cell CLL/lymphoma 11B (BCL11B). Pathway analysis revealed calcium-induced T lymphocyte apoptosis and the role of nuclear factor of activated T-cells (NFAT) in regulation of the immune response as the most inhibited pathways, while apoptosis signaling was significantly activated. Most of the normal biofunctions were significantly decreased while cell death and survival process were activated. Gene ontology enrichment analysis revealed the immune system process as the most overrepresented group under the biological process category. Toxicity function analysis identified liver, kidney and heart to be the most affected organs during and after radiation therapy. The identified biomarkers and alterations in molecular pathways induced by radiation therapy should be further investigated to reduce the cytotoxicity and development of fatigue.

A proteomics based approach for the identification of gastric cancer related markers

Gastric cancer (GC) is the amongst the most common cancer types causing second largest number of cancer related deaths globally. GC is characterized as an aggressive malignancy which is very tough to be detected at an early stage. GC has been defined as a complex, multistep process involving multiple genetic and epigenetic alterations leading to aberrant expression of key regulating factors. GC according to WHO has been defined as malignant epithelial tumors of the gastric mucosa with glandular differentiation. About one half of the GCs are located in the lower stomach, and remaining is located in the corpus and fundus of the stomach (20%), lesser curvature (20%), cardia (10%) and greater curvature (3%). GC has been classified into intestinal and diffuse types based on epidemiological and clinico- and histopathological features. The etiology of GC is multifactorial and includes dietary as well as non-dietary factors. Despite a lot of research efforts, GC remains to be the cancer without clear symptoms at onset, poor prognosis, with metastasis and recurrence. Thus, there is an urgent need for identifying novel and diagnostic GC biomarkers and techniques with high sensitivity and specificity. In the present review, we provide a synopsis of proteomics based GC biomarkers discovered from various cancerous specimens such as blood, gastric fluid, tissues, cells and H. pylori infected cancer cell lines. The advent of proteomics based GC biomarkers will be a great asset for the early detection and treatment of GC.