Comparison of Wet Fractionation Methods for Processing Broccoli Agricultural Wastes and Evaluation of the Nutri-Chemical Values of Obtained Products.

The main objective of this study was to increase the economic value of broccoli green agro-waste using three wet fractionation methods in the shadow of green biorefinery and the circular economy. Product candidates were obtained directly by using a mechanical press, and indirectly by using microwave coagulation or via lactic acid fermentation of green juice. The leaf protein concentrates (LPC) fractions displayed significantly higher dry matter content and crude protein content (34-39 m/m% on average) than the green juice fraction (27.

Thyrotropin-releasing hormone selectively stimulates human hair follicle pigmentation.

In amphibians, thyrotropin-releasing hormone (TRH) stimulates skin melanophores by inducing secretion of α-melanocyte-stimulating hormone in the pituitary gland. However, it is unknown whether this tripeptide neurohormone exerts any direct effects on pigment cells, namely, on human melanocytes, under physiological conditions. Therefore, we have investigated whether TRH stimulates pigment production in organ-cultured human hair follicles (HFs), the epithelium of which expresses both TRH and its receptor, and/or in full-thickness human skin in situ.

Thyroid-stimulating hormone, a novel, locally produced modulator of human epidermal functions, is regulated by thyrotropin-releasing hormone and thyroid hormones.

Several elements of the hypothalamic-pituitary-thyroid axis (HPT) reportedly are transcribed by human skin cell populations, and human hair follicles express functional receptors for TSH. Therefore, we asked whether the epidermis of normal human skin is yet another extrathyroidal target of TSH and whether epidermis even produces TSH. If so, we wanted to clarify whether intraepidermal TSH expression is regulated by TRH and/or thyroid hormones and whether TSH alters selected functions of normal human epidermis in situ.

Thyrotropin powers human mitochondria.

Here we demonstrate that the neuropeptide hormone thyrotropin (TSH), which controls thyroid hormone production, exerts a major nonclassical function in mitochondrial biology. Based on transcriptional, ultrastructural, immunohistochemical, and biochemical evidence, TSH up-regulates mitochondrial biogenesis and consequently activity in organ-cultured normal human epidermis in situ. Mitochondrial activity was assessed by measuring 2 key components of the respiratory chain.

Corticotropin-releasing hormone stimulates the in situ generation of mast cells from precursors in the human hair follicle mesenchyme.

Hair follicles (HFs) maintain a peripheral, functional equivalent of the hypothalamic-pituitary-adrenal (HPA) axis, whose most proximal element is corticotropin-releasing hormone (CRH). The mast cell (MC)-rich connective-tissue sheath (CTS) of mouse vibrissa HFs harbors MC precursors. Differentiation of these MC precursors into mature MCs can be induced by stem cell factor (SCF).

A simple assay for the study of human hair follicle damage induced by ionizing irradiation.

Due to its rapidly proliferating matrix keratinocytes, the hair follicle is highly sensitive to ionizing irradiation (IR)-induced skin damage and thus an instructive and clinically relevant model organ for investigating the effects of IR on rapidly dividing epithelial-mesenchymal interaction systems. Here, we have assessed the impact of IR on organ-cultured human scalp hair follicles. We show that IR significantly inhibits the proliferation and induces apoptosis of hair follicle matrix keratinocytes, disrupts normal hair follicle pigmentation, and upregulates a number of quantitative toxicity and viability markers (oxidative stress indicators, DNA oxidative damage, LDH release).

Thyrotropin releasing hormone (TRH): a new player in human hair-growth control.

Thyrotropin-releasing hormone (TRH) is the most proximal component of the hypothalamic-pituitary-thyroid axis that regulates thyroid hormone synthesis. Since transcripts for members of this axis were detected in cultured normal human skin cells and since human hair follicles (HFs) respond to stimulation with thyrotropin, we now have studied whether human HF functions are also modulated by TRH. Here we report that the epithelium of normal human scalp HFs expresses not only TRH receptors (TRH-R) but also TRH itself at the gene and protein level.

Does erythropoietin modulate human hair follicle melanocyte activities in situ?

Erythropoietin (EPO) is now appreciated for not only drive erythopoiesis, but also to exert additional functions. Since we had previously shown that human hair follicles (HFs) are both an extra-renal source and an extra-medullary target of EPO, we have now studied whether one such function is the regulation of HF pigmentation. Human anagen VI HFs were treated with EPO (100 IU/ml) in serum-free organ culture.

Leptin and the skin: a new frontier.

Here, we examine the currently available information which supports that the adipokine, leptin, is a major player in the biology and pathology of mammalian skin and its appendages. Specifically, the potent metabolic effects of leptin and its mimetics may be utilized to improve, preserve and restore skin regeneration and hair cycle progression, and may halt or even partially reverse some aspects of skin ageing. Since leptin can enhance mitochondrial activity and biogenesis, this may contribute to the wound healing-promoting and hair growth-modulatory effects of leptin.

Erythropoietin and the skin: a role for epidermal oxygen sensing?

Erythropoietin (EPO), long appreciated as the chief endocrine regulator of red blood cell formation, is now recognized to exert many additional functions outside the bone marrow. Thus, the quest is on to define the full range of EPO functions in the physiology and pathology of non-hematopoietic tissues. Two recent studies in man and mice have highlighted the importance of the mammalian skin as one peripheral tissue with a previously unsuspected role in EPO biology; both, as a target and as a source of EPO.

Keratinocyte-derived follistatin regulates epidermal homeostasis and wound repair.

Activin is a growth and differentiation factor that controls development and repair of several tissues and organs. Transgenic mice overexpressing activin in the skin were characterized by strongly enhanced wound healing, but also by excessive scarring. In this study, we explored the consequences of targeted activation of activin in the epidermis and hair follicles by generation of mice lacking the activin antagonist follistatin in keratinocytes.

Human female hair follicles are a direct, nonclassical target for thyroid-stimulating hormone.

Pituitary thyroid-stimulating hormone (TSH) regulates thyroid hormone synthesis via receptors (TSH-R) expressed on thyroid epithelial cells. As the hair follicle (HF) is uniquely hormone-sensitive and, hypothyroidism with its associated, increased TSH serum levels clinically can lead to hair loss, we asked whether human HFs are a direct target for TSH. Here, we report that normal human scalp skin and microdissected human HFs express TSH-R mRNA.

A human folliculoid microsphere assay for exploring epithelial- mesenchymal interactions in the human hair follicle.

The search for more effective drugs for the management of common hair growth disorders remains a top priority, both for clinical dermatology and industry. In this pilot study, we report a pragmatic organotypic assay for basic and applied hair research. The patented technique produces microdroplets, which generate human folliculoid microspheres (HFMs), consisting of human dermal papilla fibroblasts and outer root sheath keratinocytes within an extracellular matrix that simulates elements of the hair follicle mesenchyme.

Thyroid hormones directly alter human hair follicle functions: anagen prolongation and stimulation of both hair matrix keratinocyte proliferation and hair pigmentation.

Context: Both insufficient and excess levels of thyroid hormones (T3 and T4) can result in altered hair/skin structure and function (e.g. effluvium).

T-oligos as differential modulators of human scalp hair growth and pigmentation: a new "time lapse system" for studying human skin and hair follicle biology in vitro?

Small DNA oligonucleotides homologous to the 3' overhang of human telomeres, called T-oligos, stimulate pigmentation in human epidermal melanocytes in vitro and in vivo. They induce UV-mimetic effects in the absence of DNA-damage, however, it is unknown how T-oligos affect human hair follicle keratinocyte and melanocyte functions in situ. Here, we present the first evidence that these oligonucleotides are powerful modulators of pigmentation and growth of microdissected, organ-cultured human scalp hair follicles.

Probing the effects of stress mediators on the human hair follicle: substance P holds central position.

Stress alters murine hair growth, depending on substance P-mediated neurogenic inflammation and nerve growth factor (NGF), a key modulator of hair growth termination (catagen induction). Whether this is of any relevance in human hair follicles (HFs) is completely unclear. Therefore, we have investigated the effects of substance P, the central cutaneous prototypic stress-associated neuropeptide, on normal, growing human scalp HFs in organ culture.

Dissecting the impact of chemotherapy on the human hair follicle: a pragmatic in vitro assay for studying the pathogenesis and potential management of hair follicle dystrophy.

Chemotherapy-induced alopecia represents one of the major unresolved problems of clinical oncology. The underlying molecular pathogenesis in humans is virtually unknown because of the lack of adequate research models. Therefore, we have explored whether microdissected, organ-cultured, human scalp hair follicles (HFs) in anagen VI can be exploited for dissecting and manipulating the impact of chemotherapy on human HFs.

Hair follicle stem cells: walking the maze.

The discovery of epithelial stem cells (eSCs) in the bulge region of the outer root sheath of hair follicles in mice and man has encouraged research into utilizing the hair follicle as a therapeutic source of stem cells (SCs) for regenerative medicine, and has called attention to the hair follicle as a highly instructive model system for SC biology. Under physiological circumstances, bulge eSCs serve as cell pool for the cyclic regeneration of the anagen hair bulb, while they can also regenerate the sebaceous gland and the epidermis after injury. More recently, melanocyte SCs, nestin+, mesenchymal and additional, as yet ill-defined "stem cell" populations, have also been identified in or immediately adjacent to the hair follicle epithelium, including in the specialized hair follicle mesenchyme (connective tissue sheath), which is crucial to wound healing.

Inhibition of human hair follicle growth by endo- and exocannabinoids.

Recent studies strongly suggest that the cannabinoid system is a key player in cell growth control. Since the organ-culture of human hair follicles (HF) offers an excellent, clinically relevant model for complex tissue interaction systems, we have asked whether the cannabinoid system plays a role in hair growth control. Here, we show that human scalp HF, intriguingly, are both targets and sources of endocannabinoids.

Human hair follicles are an extrarenal source and a nonhematopoietic target of erythropoietin.

Erythropoietin primarily serves as an essential growth factor for erythrocyte precursor cells. However, there is increasing evidence that erythropoietin (EPO)/EPO receptor (EPO-R) signaling operates as a potential tissue-protective system outside the bone marrow. Arguing that growing hair follicles (HF) are among the most rapidly proliferating tissues, we have here explored whether human HFs are sources of EPO and targets of EPO-R-mediated signaling.

Towards the development of a simplified long-term organ culture method for human scalp skin and its appendages under serum-free conditions.

Organ culture of human scalp skin is usually performed with serum-containing medium, which limits its analytical usefulness. Here we report that intact human scalp skin can be grown at the air/liquid interface in supplemented, serum-free William's E medium for more than 2 weeks. Active hair shaft growth was visible until day 16 and was significantly enhanced compared with minimum essential medium (MEM) + 10% fetal bovine serum (FBS).

Keratinocyte growth factor protects epidermis and hair follicles from cell death induced by UV irradiation, chemotherapeutic or cytotoxic agents.

Owing to its potent cytoprotective properties for epithelial cells, keratinocyte growth factor (KGF) is successfully used for the treatment of chemotherapy- and radiotherapy-induced oral mucositis in cancer patients. It is therefore of major interest to determine possible clinical applications of KGF in other organs and in different stress situations and to unravel common and organ-specific mechanisms of KGF action. Here we show that KGF protects human keratinocytes from the toxicity of xenobiotics with electrophilic and oxidative properties and reduces the cell death induced by UV irradiation.