Oxalate decarboxylase from Collybia velutipes: molecular cloning and its overexpression to confer resistance to fungal infection in transgenic tobacco and tomato

Oxalic acid is present as nutritional stress in many crop plants like Amaranth and Lathyrus. Oxalic acid has also been found to be involved in the attacking mechanism of several phytopathogenic fungi. A full-length cDNA for oxalate decarboxylase, an oxalate-catabolizing enzyme, was isolated by using 5'-rapid amplification of cDNA ends-polymerase chain reaction of a partial cDNA as cloned earlier from our laboratory (Mehta, A., and Datta, A. (1991) J. Biol. Chem. 266, 23548-23553). By screening a genomic library from Collybia velutipes with this cDNA as a probe, a genomic clone has been isolated. Sequence analyses and comparison of the genomic sequence with the cDNA sequence revealed that the cDNA is interrupted with 17 small introns. The cDNA has been successfully expressed in cytosol and vacuole of transgenic tobacco and tomato plants. The transgenic plants show normal phenotype, and the transferred trait is stably inherited to the next generation. The recombinant enzyme is partially glycosylated and shows oxalate decarboxylase activity in vitro as well as in vivo. Transgenic tobacco and tomato plants expressing oxalate decarboxylase show remarkable resistance to phytopathogenic fungus Sclerotinia sclerotiorum that utilizes oxalic acid during infestation. The result presented in the paper represents a novel approach to develop transgenic plants resistant to fungal infection

Development of a novel HPTLC fingerprint method for simultaneous estimation of berberine and rutin in medicinal plants and their pharmaceutical preparations followed by its application in antioxidant assay

The present study was designed to develop and validate a high-performance thin-layer chromatography (HPTLC) system for the simultaneous quantitative determination of berberine and rutin in Tinospora cordifolia extract and their pharmaceutical preparations. Chromatographic development was done using a blend of n-hexane, ethyl acetate, glacial acetic acid and methanol (10:1.1:1.1:2.5, v/v) as the mobile phase. Detection was completed densitometrically at 254 nm. The RF estimation of berberine and rutin was observed to be 0.67 ± 0.02 and 0.47 ± 0.02, respectively. The developed HPTLC method was validated according to ICH guidelines; the method was specific, linear and accurate and can be used to determine berberine and rutin in marketed herbal preparations. The Tinospora cordifolia plant extract was further evaluated for antioxidant activity using HPTLC, and berberine was found to be more active than rutin during DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity. The method was found simple, rapid, accurate, specific and robust for the analysis of berberine and rutin in crude drug using the same method

Plants derived therapeutic strategies targeting chronic respiratory diseases: Chemical and immunological perspective

The apparent predicament of the representative chemotherapy for managing respiratory distress calls for an obligatory deliberation for identifying the pharmaceuticals that effectively counter the contemporary intricacies associated with target disease. Multiple, complex regulatory pathways manifest chronic pulmonary disorders, which require chemotherapeutics that produce composite inhibitory effect. The cost effective natural product based molecules hold a high fervor to meet the prospects posed by current respiratory-distress therapy by sparing the tedious drug design and development archetypes, present a robust standing for the possible replacement of the fading practice of poly-pharmacology, and ensure the subversion of a potential disease relapse. This study summarizes the experimental evidences on natural products moieties and their components that illustrates therapeutic efficacy on respiratory disorders

Role of Serine/Threonine Kinase 11 (STK11) or liver kinase B1 (LKB1) Gene in Peutz-Jeghers Syndrome

Peutz-Jeghers syndrome (PJS) is a well-described inherited syndrome, characterized by the development of gastrointestinal polyps and characteristic mucocutaneous freckling. PJS is an autosomal prevailing disease, due to genetic mutation on chromosome 19p, manifested by restricted mucocutaneous melanosis in association with gastrointestinal (GI) polyposis. The gene for PJS has recently been shown to be a serine/threonine kinase, known as LKB1 or STK11, which maps to chromosome subband 19p13.3. This gene has a putative coding region of 1302 bp, divided into nine exons, and acts as a tumor suppressor in the hamartomatous polyps of PJS patients and in the other neoplasms that develop in PJS patients. It is probable that these neoplasms develop from hamartomas, but it remains possible that the LKB1 or STK11 locus plays a role in a different genetic pathway of tumor growth in the cancers of PJS patients. This article focuses on the role of LKB1 or STK11 gene expression in PJS and related cancers

Hypoxia-inducible factor (HIF): fuel for cancer progression

Hypoxia is an integral part of the tumor microenvironment, caused primarily due to rapidly multiplying tumor cells and a lack of proper blood supply. Among the major hypoxic pathways, HIF-1 transcription factor activation is one of the widely investigated pathways in the hypoxic tumor microenvironment (TME). HIF-1 is known to activate several adaptive reactions in response to oxygen deficiency in tumor cells. HIF-1 has two subunits, HIF-1β (constitutive) and HIF-1α (inducible). The HIF-1α expression is largely regulated via various cytokines (through PI3K-ACT-mTOR signals), which involves the cascading of several growth factors and oncogenic cascades. These events lead to the loss of cellular tumor suppressant activity through changes in the level of oxygen via oxygen-dependent and oxygenindependent pathways. The significant and crucial role of HIF in cancer progression and its underlying mechanisms have gained much attention lately among the translational researchers in the fields of cancer and biological sciences, which have enabled them to correlate these mechanisms with various other disease modalities. In the present review, we have summarized the key findings related to the role of HIF in the progression of tumors

Cellular signalling pathways mediating the pathogenesis of chronic inflammatory respiratory diseases: an update

Respiratory disorders, especially non-communicable, chronic inflammatory diseases, are amongst the leading causes of mortality and morbidity worldwide. Respiratory diseases involve multiple pulmonary components, including airways and lungs that lead to their abnormal physiological functioning. Several signaling pathways have been reported to play an important role in the pathophysiology of respiratory diseases. These pathways, in addition, become the compounding factors contributing to the clinical outcomes in respiratory diseases. A range of signaling components such as Notch, Hedgehog, Wingless/Wnt, bone morphogenetic proteins, epidermal growth factor and fibroblast growth factor is primarily employed by these pathways in the eventual cascade of events. The different aberrations in such cell-signaling processes trigger the onset of respiratory diseases making the conventional therapeutic modalities ineffective. These challenges have prompted us to explore novel and effective approaches for the prevention and/or treatment of respiratory diseases. In this review, we have attempted to deliberate on the current literature describing the role of major cell signaling pathways in the pathogenesis of pulmonary diseases and discuss promising advances in the field of therapeutics that could lead to novel clinical therapies capable of preventing or reversing pulmonary vascular pathology in such patients

An overview of vaccine development for COVID-19

The COVID-19 pandemic continues to endanger world health and the economy. The causative SARS-CoV-2 coronavirus has a unique replication system. The end point of the COVID-19 pandemic is either herd immunity or widespread availability of an effective vaccine. Multiple candidate vaccines - peptide, virus-like particle, viral vectors (replicating and nonreplicating), nucleic acids (DNA or RNA), live attenuated virus, recombinant designed proteins and inactivated virus - are presently under various stages of expansion, and a small number of vaccine candidates have progressed into clinical phases. At the time of writing, three major pharmaceutical companies, namely Pfizer and Moderna, have their vaccines under mass production and administered to the public. This review aims to investigate the most critical vaccines developed for COVID-19 to date

Pharmacological properties of bergapten: mechanistic and therapeutic aspects

Bergapten (BP) or 5-methoxypsoralen (5-MOP) is a furocoumarin compound mainly found in bergamot essential oil but also in other citrus essential oils and grapefruit juice. This compound presents antibacterial, anti-inflammatory, hypolipemic, and anticancer effects and is successfully used as a photosensitizing agent. The present review focuses on the research evidence related to the therapeutic properties of bergapten collected in recent years. Many preclinical and in vitro studies have been evidenced the therapeutic action of BP; however, few clinical trials have been carried out to evaluate its efficacy. These clinical trials with BP are mainly focused on patients suffering from skin disorders such as psoriasis or vitiligo. In these trials, the administration of BP (oral or topical) combined with UV irradiation induces relevant lesion clearance rates. In addition beneficial effects of bergamot extract were also observed in patients with altered serum lipid profiles and in people with nonalcoholic fatty liver. On the contrary, there are no clinical trials that investigate the possible effects on cancer. Although the bioavailability of BP is lower than that of its 8-methoxypsoralen (8-MOP) isomer, it has fewer side effects allowing higher concentrations to be administered. In conclusion, although the use of BP has therapeutic applications on skin disorders as a sensitizing agent and as components of bergamot extract as hypolipemic therapy, more trials are necessary to define the doses and treatment guidelines and its usefulness against other pathologies such as cancer or bacterial infections.info:eu-repo/semantics/publishedVersio