Other affiliations: Semmelweis University
Bio: Chandana Haldar is an academic researcher from Banaras Hindu University. The author has contributed to research in topic(s): Melatonin & Pineal gland. The author has an hindex of 25, co-authored 161 publication(s) receiving 1964 citation(s). Previous affiliations of Chandana Haldar include Semmelweis University.
Topics: Melatonin, Pineal gland, Melatonin receptor, Oxidative stress, Receptor
Papers published on a yearly basis
TL;DR: The results propose anticancer efficacy of PLA-Qt nanoparticles in terms of its sustained release kinetics revealing novel vehicle for the treatment of cancer.
Abstract: This study was carried out to synthesize quercetin (Qt) embedded poly(lactic acid) (PLA) nanoparticles (PLA–Qt) and to evaluate anti-cancer efficacy of PLA–Qt by using human breast cancer cells. PLA–Qt were synthesized by using novel emulsified nanoprecipitation technique with varying dimension of 32 ± 8 to 152 ± 9 nm of PLA–Qt with 62 ± 3% (w/w) entrapment efficiency by varying the concentration of polymer, emulsifier, drug and preparation temperature. The dimension of PLA–Qt was measured through transmission electron microscopy indicating larger particle size at higher concentration of PLA. The release rate of Qt from PLA–Qt was found to be more sustained for larger particle dimension (152 ± 9 nm) as compared to smaller particle dimension (32 ± 8 nm). Interaction between Qt and PLA was verified through spectroscopic and calorimetric methods. Delayed diffusion and stronger interaction in PLA–Qt caused the sustained delivery of Qt from the polymer matrix. In vitro cytotoxicity study indicate the killing of ∼50% breast cancer cells in two days at 100 μg/ml of drug concentration while the ∼40% destruction of cells require 5 days for PLA–Qt (46 ± 6 nm; 20 mg/ml of PLA). Thus our results propose anticancer efficacy of PLA–Qt nanoparticles in terms of its sustained release kinetics revealing novel vehicle for the treatment of cancer.
TL;DR: Melatonin--one of the universally accepted chronobiotic molecule secreted by the pineal gland is now emerging as one of the most effective immunostimulatory compound in rodents and as oncostatic molecule at least in human.
Abstract: The seasons, and daily physical rhythms can have a profound effect on the physiology of the living organism, which includes immune status. The immune system can be influenced by a variety of signals and one of them is photic stimulus. Light may regulate the immunity through the neuroendocrine system leading to the most recent branch of research the “Photoimmunomodulation”. Mammals perceive visible light (400–700 nm) through some specialized photoreceptors located in retina like retinal ganglion cells (RGC). This photic signal is then delivered to the visual cortex from there to the suprachiasmatic nucleus (SCN) of the hypothalamic region. Melatonin – one of the universally accepted chronobiotic molecule secreted by the pineal gland is now emerging as one of the most effective immunostimulatory compound in rodents and as oncostatic molecule at least in human. Its synthesis decreases with light activation along with norepinephrine and acetylcholine. The changes in level of melatonin may lead to alterations (stimulatory/inhibitory) in immune system. The evidences for the presence of melatonin receptor subtypes on lymphoid tissues heralded the research area about mechanism of action for melatonin. Further, melatonin receptor subtypes-MT1 and MT2 was noted on pars tuberalis, SCN and on lymphatic tissues suggesting a direct action of melatonin in modulation of immunity by photoperiod as well. The nuclear receptors (ROR, RZR etc.) of melatonin are known for its free radical scavenging actions and might be indirectly controlling the immune function.
TL;DR: Seasonal levels of melatonin act like a major temporal synchronizer to maintain not only the seasonal reproduction but also immune adaptability of this avian species.
Abstract: Seasonal changes in pineal function are well coordinated with seasonal reproductive activity of tropical birds. Further, immunomodulatory property of melatonin is well documented in seasonally breeding animals. Present study elucidates the interaction of peripheral melatonin with seasonal pattern of immunity and reproduction in Indian tropical male bird Perdicula asiatica. Significant seasonal changes were noted in pineal, testicular and immune function(s) of this avian species. Maximum pineal activity along with high immune status was noted during winter month while maximum testicular activity with low immune status was noted in summer. During summer month's long photoperiod suppressed pineal activity and high circulating testosterone suppressed immune parameters, while in winter short photoperiod elevated pineal activity and high circulating melatonin maintained high immune status and suppressed gonadal activity. Therefore, seasonal levels of melatonin act like a major temporal synchronizer to maintain not only the seasonal reproduction but also immune adaptability of this avian species.
TL;DR: Exogenous melatonin with its anti-apoptotic and antioxidant properties additively increased the immunity of the squirrels, by protecting their hematopoietic system and lymphoid organs against X-ray radiation induced cellular toxicity.
Abstract: Purpose: The radioprotective ability of melatonin was investigated in the Indian tropical rodent, Funambulus pennanti during its reproductively inactive phase (RIP) when peripheral melatonin is high and the animal is under the influence of environmental stresses. Materials and methods: Fifty male squirrels were divided into two sets of 25 each; with set 1 receiving 0.9% saline and set 2 receiving 25 mg melatonin/100 g body weight/day for four weeks during evening hours. Five saline-treated and five-melatonin treated squirrels were sacrificed at times of 4, 24, 48 and 72 hours following 2.06 Gy X-ray radiation. Remaining squirrels that were not exposed to X-ray were used as control and melatonin treated, respectively. Total leukocyte count (TLC) and lymphocyte count (LC) in peripheral blood and lipid peroxidation (LPO) status, superoxide dismutase (SOD) activity, total antioxidant status (TAS), apoptotic percentage on the basis of morphological changes and DNA fragmentation and caspase3 activity were measured in the spleens of squirrels. Results: Peripheral blood and spleens with higher intrinsic levels of environmental and X-radiation induced free radical generation had inhibited TLC, LC, SOD activity and TAS and increased LPO and apoptosis. Melatonin pre-treatment significantly reduced and altered the changes brought on by X-radiation. Conclusion: Exogenous melatonin with its anti-apoptotic and antioxidant properties additively increased the immunity of the squirrels, by protecting their hematopoietic system and lymphoid organs against X-ray radiation induced cellular toxicity.
01 Aug 2013-Journal of Porous Materials
TL;DR: In-vivo study on mice finally validated the controlled rate of drug release showing the effectiveness of PEG incorporation into the scaffold for quicker and regulated wound healing.
Abstract: A novel ciprofloxacin hydrochloride loaded chitosan/poly(ethylene glycol) (PEG) composite scaffold was developed for wound dressing application PEG incorporation in chitosan scaffold showed enhanced loading up to 54 % and increased cumulative release of the drug up to 35 % as compared to pure chitosan scaffold (20 %) The drug loading and control release of the drug has been explained by the morphological features and drug–polymer/polymer–polymer interactions revealed by SEM, FTIR and DSC Bacterial growth inhibition evaluation using Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus confirmed the efficacy of released drug from the scaffolds (pure and PEG mixed chitosan) Swelling study, bacterial penetration, moisture vapour transmission rate, haematocompatibility and biodegradation profile supported the suitability of scaffold used as wound dressing materials In-vivo study on mice finally validated the controlled rate of drug release showing the effectiveness of PEG incorporation into the scaffold for quicker and regulated wound healing
01 Jan 1979
TL;DR: The different types of materials used as delivery vehicles for chemotherapeutic agents and their structural characteristics that improve the therapeutic efficacy of their drugs are discussed and recent scientific advances in the area of chemotherapy are described.
Abstract: Although conventional chemotherapy has been successful to some extent, the main drawbacks of chemotherapy are its poor bioavailability, high-dose requirements, adverse side effects, low therapeutic indices, development of multiple drug resistance, and non-specific targeting. The main aim in the development of drug delivery vehicles is to successfully address these delivery-related problems and carry drugs to the desired sites of therapeutic action while reducing adverse side effects. In this review, we will discuss the different types of materials used as delivery vehicles for chemotherapeutic agents and their structural characteristics that improve the therapeutic efficacy of their drugs and will describe recent scientific advances in the area of chemotherapy, emphasizing challenges in cancer treatments.
01 Jun 2003-Pharmacological Reviews
TL;DR: The aim of this review is to gather together early and recent data on the effects of the nonadrenergic transmitters on modulation of melatonin synthesis, which reveals the variety of inputs that can be integrated by the pineal gland; what elements are crucial to deliver the very precise timing information to the organism.
Abstract: Melatonin, the major hormone produced by the pineal gland, displays characteristic daily and seasonal patterns of secretion. These robust and predictable rhythms in circulating melatonin are strong synchronizers for the expression of numerous physiological processes in photoperiodic species. In mammals, the nighttime production of melatonin is mainly driven by the circadian clock, situated in the suprachiasmatic nucleus of the hypothalamus, which controls the release of norepinephrine from the dense pineal sympathetic afferents. The pivotal role of norepinephrine in the nocturnal stimulation of melatonin synthesis has been extensively dissected at the cellular and molecular levels. Besides the noradrenergic input, the presence of numerous other transmitters originating from various sources has been reported in the pineal gland. Many of these are neuropeptides and appear to contribute to the regulation of melatonin synthesis by modulating the effects of norepinephrine on pineal biochemistry. The aim of this review is firstly to update our knowledge of the cellular and molecular events underlying the noradrenergic control of melatonin synthesis; and secondly to gather together early and recent data on the effects of the nonadrenergic transmitters on modulation of melatonin synthesis. This information reveals the variety of inputs that can be integrated by the pineal gland; what elements are crucial to deliver the very precise timing information to the organism. This also clarifies the role of these various inputs in the seasonal variation of melatonin synthesis and their subsequent physiological function.
TL;DR: Biocompatible with fibroblasts and keratinocytes, tissue engineered skin is indicated for regeneration and remodeling of human epidermis and wound healing improving the treatment of severe skin defects or partial-thickness burn injuries.
Abstract: In the last years, health care professionals faced with an increasing number of patients suffering from wounds and burns difficult to treat and heal. During the wound healing process, the dressing protects the injury and contributes to the recovery of dermal and epidermal tissues. Because their biocompatibility, biodegradability and similarity to macromolecules recognized by the human body, some natural polymers such as polysaccharides (alginates, chitin, chitosan, heparin, chondroitin), proteoglycans and proteins (collagen, gelatin, fibrin, keratin, silk fibroin, eggshell membrane) are extensively used in wounds and burns management. Obtained by electrospinning technique, some synthetic polymers like biomimetic extracellular matrix micro/nanoscale fibers based on polyglycolic acid, polylactic acid, polyacrylic acid, poly-ɛ-caprolactone, polyvinylpyrrolidone, polyvinyl alcohol, polyethylene glycol, exhibit in vivo and in vitro wound healing properties and enhance re-epithelialization. They provide an optimal microenvironment for cell proliferation, migration and differentiation, due to their biocompatibility, biodegradability, peculiar structure and good mechanical properties. Thus, synthetic polymers are used also in regenerative medicine for cartilage, bone, vascular, nerve and ligament repair and restoration. Biocompatible with fibroblasts and keratinocytes, tissue engineered skin is indicated for regeneration and remodeling of human epidermis and wound healing improving the treatment of severe skin defects or partial-thickness burn injuries.