Approaches in biotechnological applications of natural polymers

Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)

Progesterone as a morphological regulatory factor of the male and female gerbil prostate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Testosterone (T) and oestrogen are the main active steroid hormones in the male and female reproductive system respectively. In female rodents progesterone (P4), together with testosterone and oestrogen, has an essential role in the regulation of the oestrous cycle, which influences the prostate physiology through their oscillations. In this work we investigated how the male and female prostate gland of Mongolian gerbils responds to surgical castration at the start of puberty and what are the effects of T, oestradiol (E2) and P4 replacement, using both quantitative and qualitative methods. We also examined the location of the main steroid receptors present in the prostate. In the castrated animals of both sexes an intense glandular regression, along with disorganization of the stromal compartment, and abundant hyperplasia was observed. The replacement of P4 secured a mild recovery of the glandular morphology, inducing the growth of secretory cells and restoring the androgen receptor (AR) cells. The administration of P4 and E2 eliminated epithelial hyperplasia and intensified gland hypertrophy, favouring the emergence of prostatic intraepithelial neoplasia (PIN). In animals treated with T and P4, even though there are some inflammatory foci and other lesions, the prostate gland revealed morphology closer to that of control animals. In summary, through the administration of P4, we could demonstrate that this hormone has anabolic characteristics, promoting hyperplasia and hypertrophy, mainly in the epithelial compartment. When combined with E2 and T, there is an accentuation of glandular hypertrophy that interrupts the development of hyperplasia and ensures the presence of a less dysplastic glandular morphology.946373386Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [2008/11386-9]CNPq [301596/2011-5

Experimental endocrine therapies promote epithelial cytodifferentiation and ciliogenesis in the gerbil female prostate

The incidence of ciliated cells in the prostate gland of the female gerbil (Meriones unguiculatus) is uncommon and apparently becomes more frequent during androgen (testosterone cypionate) and anti-estrogen (letrozole) endocrine therapies. To evaluate the effects of such drug therapies on the induction of ciliogenesis in the glandular epithelium of female prostate glands, adult female gerbils aged 90 days were treated for 14 days with testosterone and letrozole after which their prostate glands were removed for histological, ultrastructural, and serological analyses. The cytodifferentiation of the ciliated phenotype in the alveolar epithelium became more frequent after both the testosterone and the letrozole treatments. The ciliogenesis phenomenon of the epithelial cells in the prostate gland of female gerbils thus appears to be induced by variations in the increase of androgen levels.328361762

Antiestrogen therapies affect tissue homeostasis of the gerbil (Meriones unguiculatus) female prostate and ovaries

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The present work aims to evaluate the response of the adult gerbil female prostate (paraurethral glands) and ovaries to short-term exposure to antiestrogenic agents, consisting of daily oral doses of letrozole (1 mg kg(-1) day(-1)) or intradermal doses of tamoxifen (1 mg/kg) every other day for 21 days. The serum levels of testosterone and estradiol were monitored, and the prostates and ovaries collected for structural, ultrastructural, and immunocytochemical analyses. The letrozole treatment resulted in increases of serum testosterone levels and secretory activity as well as in glandular hyperplasia and dysplastic growth, simulating the effects caused by the exogenous androgens. The effects caused by tamoxifen indicate that this endocrine agent acted as an estrogenic agonist on the prostate, causing glandular hypertrophy, secretory activity decrease, and the development of prostatic lesions. Therefore, it is possible to conclude that the letrozole and tamoxifen therapies result in a series of complex effects that endanger the physiology of hormone-dependent organs, including the female prostate and ovaries. The hormonal imbalance caused by administration of these drugs resulted in considerable changes in prostatic morphology, in a manner very similar to what occurs during the development of prostatic lesions in aged postmenopausal women. Thus, these therapies must be chosen carefully since long-term treatments can result in female prostate dysplasic lesions.794674685Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)CNPq [301111/05-7]FAPESP [02/12942-6