Assay for lipid peroxides in animal tissues by thiobarbituric acid reaction

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.

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Controlled drug delivery vehicles for cancer treatment and their performance.

Textbook of histology

Natural and synthetic polymers for wounds and burns dressing

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.

Generation of the Melatonin Endocrine Message in Mammals: A Review of the Complex Regulation of Melatonin Synthesis by Norepinephrine, Peptides, and Other Pineal Transmitters

Pregnancy is associated with profound immunological changes that are characterized by a strong activation of certain components of the innate immune defense and a down-regulation of adaptive immune functions. This shift in balance of the immune system towards an innate dominance is thought to be important for the maintenance of pregnancy. Based on our observation in the short nosed fruit bat Cynopterus sphinx, a seasonal breeder, we show for the first time that melatonin injection to the pregnant females significantly increases lymphocyte proliferation of spleen and consequently the circulating level of lymphocytes and percent stimulation ratio of splenocytes, thereby improving immune status during pregnancy. We have reported earlier that during pregnancy melatonin level increases significantly which in turn might improve the maternal immunity. Towards establishing this inference we used a physiological dose of p-chlorophenylalanine (p-CPA), an indirect antagonist of melatonin, which reduced circulatory melatonin level and thereby reduced the immune status. It is conceived that specific immune adaptation is conveyed to the fetus through placental transfer of melatonin thereby controlling fetal immunity as well. This could be an adaptation during pregnancy to protect the mother from various external threats.

Role of Melatonin in Modulation of Immune Status of Pregnant Female Indian Short Nosed Fruit Bat Cynopterus Sphinx

Photoperiod modulates reproductive physiology at multiple levels in seasonally breeding animals. Golden hamsters are long-day breeders that diminish their fertility during the short days. Photoperiod is known to regulate hormonal milieu and uterus is a hormone-sensitive dynamic tissue. However, there is lack of molecular insight regarding the impact of photoperiod on uterine physiology with respect to redox and metabolic status in Mesocricetus auratus. We evaluated the impact of photoperiod on circulatory hormonal parameters (triiodothyronine [T3], thyroxin [T4], estradiol [E2], progesterone [P4], melatonin, and insulin), their receptor expressions and key markers associated with redox (SIRT-1/FOXO-1), inflammatory (NFĸB/COX-2) and metabolic (IR/GLUT4) status in uterus. Adult female golden hamsters were exposed to different photoperiodic regimes, that is, short photoperiod (SP; 8L:16D) and long photoperiod (LP; 16L:8D) for 12 weeks. SP drastically decreased peripheral hormone profiles (T3, T4, E2, and P4) and compromised uterine histoarchitecture when compared with LP-exposed hamsters. Further, SP markedly decreased thyroid hormone receptor-α (TRα), insulin receptor, and glucose uptake transporter-4 (GLUT-4) expressions in uterus. We noted enhanced uterine oxidative (increased MDA and decreased SOD/CAT levels), SIRT-1/FOXO-1 expression and inflammatory (NFĸB/COX-2) load in SP condition. Further, elevated levels of circulatory insulin, melatonin, and its receptor (MT-1) expression in uterus was noted under SP condition. Thus, we may suggest that photoperiod might regulate uterine seasonality through modulation of local hormonal and redox/metabolic homeostasis thereby may restrict offspring bearing capacity under short days.

Impact of photoperiod on uterine redox/inflammatory and metabolic status of golden hamster, Mesocricetus auratus.

Objective: Lymphoid organs (i.e. spleen and thymus) are important due to functional dynamicity. As a result, the generated free radicals may limit their function. Thus, present study was aimed to note seasonal and sex dependent variation in free radical status in Indian goat Capra hircus under the aegis of melatonin which is a well-known antioxidant. Methods: Markers of oxidative stress (i.e. Super Oxide Dismutase; SOD, Catalase; CAT, Glutathione Peroxidases; GPx) were measured by standardized protocols. Total Antioxidant Status (TAS) was measured by 2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid; ABTS) radical cation method and Lipid Per Oxidation (LPO) was measured by Thiobarbituric acid reactive substances (TBARS) level. Glucocorticoid Receptor (GR) expression in lymphoid organs was noted by Western Blot analysis. The circulatory level of cortisol and melatonin were estimated by commercial ELISA kits. Results: We noted significantly high levels of SOD, Catalase, GPx activities and ABTS level in lymphoid organs during monsoon and low during winter. Malonaldehyde; MDA a marker for lipid peroxidation was significantly high during summer and was significantly low during monsoon and winter. Cortisol level was significantly high during monsoon whereas melatonin level was significantly high during winter. GR expression was significantly high in males during monsoon and winter, but the level was significantly high only during monsoon in females. Conclusion: All the results suggest that monsoon and winter are the seasons of stress and to buffer the elevated stress level, melatonin coupled both the roles of free radical scavenger (as a free molecule) and elevation of antioxidant enzymes.

Free radical load in lymphoid organs (spleen and thymus) of indian goat capra hircus: role of sex, season and melatonin

The Indian pygmy field mouse, Mus terricolor, is a tiny, yet economically and ecologically important crop pest found throughout South-East Asia. There are no systematic reports exploring its reproductive physiology. We report the presence of distinct periods of annual reproductive activity and quiescence in M. terricolor. Body weight in males and females, relative weights of testis, epididymis and seminal vesicle in males, ovarian and uterine weight in females, gonadal histomorphic changes, testicular and ovarian cholesterol, sialic acid in epididymis, fructose in seminal vesicle, uterine protein content, melatonin in males and females, testosterone in males, estradiol, and progesterone in females were studied over a period of three years in both wild-caught and lab-acclimated mice. The number of Graafian follicles and corpora lutea, and plasma estradiol and progesterone, along with relative weights of ovary and uterus in females exhibited a peak in the months of October–January, compared to June. Based o...

Reproductive seasonality in the Indian pygmy field mouse, Mus terricolor

Mostly studied in the hamster, the Harderian gland (HG, an extra-orbital gland) has been shown to be capable of melatonin (MEL) synthesis and to possess steroid receptor binding sites. Sexual dimorphism and ability to respond to steroid hormones have been reported for HG of some temperate zone mammals. However, to date there is no report on functional relation of HG with pineal, pituitary and gonad in any rodent. Hence, we tested the effect of gonadotropins [FSH (10μg) + LH (10μg)] and steroids [testosterone (100μg) and 17-β estradiol (50μg)] on HG function in relation to the activities of the pineal gland and gonad in both sexes of Indian palm squirrel Funambulus pennanti during the sexually quiescent phase. In general, squirrels treated with gonadotropins and gonadal steroids showed a significant increase in gonadal weight and decrease in pineal weight and plasma melatonin level in LH- and testosterone-treated groups only. There was no change in the weight of HG on FSH treatment. Porphyrin content of HG decreased after testosterone and estradiol treatment. Pineal gland weight invariably decreased after treatment with gonadotropins and testosterone. Plasma testosterone and estradiol levels increased but melatonin level decreased in all treated groups. Our data suggest that in this tropical rodent gonadotropins have an indirect effect on HG and that gonadal steroids have significant effect on HG through the influence on gonadal and pineal functions.

Effect of Gonadotropins and Gonadal Steroids (17β-Estradiol and Testosterone) on Harderian Gland Porphyrin Content and Circulatory Hormones in Indian Palm Squirrel Funambulus pennanti

Chandana Haldar

Papers

Role of Melatonin in Modulation of Immune Status of Pregnant Female Indian Short Nosed Fruit Bat Cynopterus Sphinx

Impact of photoperiod on uterine redox/inflammatory and metabolic status of golden hamster, Mesocricetus auratus.

Free radical load in lymphoid organs (spleen and thymus) of indian goat capra hircus: role of sex, season and melatonin

Reproductive seasonality in the Indian pygmy field mouse, Mus terricolor

Effect of Gonadotropins and Gonadal Steroids (17β-Estradiol and Testosterone) on Harderian Gland Porphyrin Content and Circulatory Hormones in Indian Palm Squirrel Funambulus pennanti