Wyniki wyszukiwania

1

The changes of proteoglycans during the hair cycle in the mink skin

100%

Pak J., Nakamura F., Kondo K.

Zeszyty Naukowe. Przegląd Hodowlany

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1996

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tom 29

2

Fur development in early and late born blue fox [Alopex lagopus]

86%

Blomstedt L.

Zeszyty Naukowe. Przegląd Hodowlany

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1996

|

tom 29

3

Splenic aumelanin differs from hair eumelanin in C57BL-6 mice

72%

Plonka P. M., Michalczyk D., Popik M., Handjiski B., Slominski A., Paus R.

Acta Biochimica Polonica

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2005

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tom 52

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nr 2

The presence of melanin in spleens of black C57BL/6 mice has been known for long. Although its origin and biological functions are still obscure, the relation of splenic melanin to the hair follicle and skin pigmentation was suggested. Here, we demonstrated using for the first time electron paramagnetic resonance spectroscopy that black-spotted C57BL/6 spleens contain eumelanin. Its presence here is a “yes or no” phenomenon, as even in the groups which revealed the highest percentage of spots single organs completely devoid of the pigment were found. Percentage of the spotted spleens decreased, however, with the progress of telogen after spontaneously-induced hair growth. The paramagnetic properties of the spleen eumelanin differed from the hair shaft or anagen VI skin melanin. The splenic melanin revealed narrower signal, and its microwave power saturability betrayed more heterogenous population of paramagnetic centres than in the skin or hair shaft pigment. Interestingly, the pigment of dry hair shafts and of the wet tissue of depilated anagen VI skin revealed almost identical properties. The properties of splenic melanin better resembled the synthetic dopa melanin (water suspension, and to a lesser degree – powder sample) than the skin/hair melanin. All these findings may indicate a limited degradation of splenic melanin as compared to the skin/hair pigment. The splenic eumelanin may at least in part originate from the skin melanin phagocyted in catagen by the Langerhans cells or macrophages and transported to the organ.

4

Splenic melanosis during normal murine C57BL/6 hair cycle and after chemotherapy

58%

Michalczyk-Wetula D., Salwinski A., Popik M., Jakubowska M., Plonka P. M.

Acta Biochimica Polonica

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2013

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tom 60

|

nr 3

Cancer chemotherapy is associated with serious side effects, including temporary hair loss and impairment of pigmentation. We suspect that ectopic melanin deposition occurring due to chemotherapy may add to these effects worsening the already unpleasant symptoms. We associated the ectopic occurrence of follicular melanin after chemotherapy with splenic melanosis - an interesting example of extradermal melanin localization - and we expected an increase in splenic melanin deposition after chemotherapy. Using the C57BL/6 murine model of synchronized hair cycle induced by depilation, we visualized splenic melanin by means of several histological and histochemical protocols of staining: hematoxylin and eosin, May-Grünwald-Giemsa and Fontana-Masson. Unexpectedly, the splenic deposition of melanin decreased due to application of cyclophosphamide (i.p. 120 mg/ kg body weight on day 9 post depilation). The drop was abrupt and lasted for at least 5 days (day 13-18 post depilation), as compared with normal hair cycle. Moreover, in mice with normal, depilation-induced hair cycle we observed a similar drop shortly before entering catagen (day 15 post depilation), followed by a slow and partial increase in splenic melanization up to day 27 post depilation in both groups. We conclude that cyclophosphamide negatively affects splenic melanization and/or extradermal transfer of ectopic melanin from the dystrophic hair follicles, but the most powerful down-regulator of splenic melanosis is normal and dystrophic catagen - the phase of hair follicle involution and re-modelling.

5

Extradermal melanin transfer? Lack of macroscopic spleen melanization in old C57BL-6 mice with de-synchronized hair cycle

58%

Michalczyk D., Popik M., Salwinski A., Plonka P. M.

Acta Biochimica Polonica

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2009

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tom 56

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nr 2

343-353

In quest of alternate, extradermal path of melanin transfer from skin to the visceral organs, we suggested that some portions of such melanin may be deposited in the spleen, which in young black C57BL/6 mice is often melanized. Here, we confirm these observation using young C57BL/6 female mice (up to 17 weeks) and show that this phenomenon cannot be observed in old animals where the hair cycle is not synchronized any more. The experiments were carried out both on spontaneous and depilation-induced hair cycle. We have checked it as a side-observation over many other experiments carried out on young and old C57BL/6 female mice (up to 2.5 years of life). The presence or absence of melanin in the spleens was checked macroscopically, and histologically by Fontana-Masson (FM) staining, and synchronization of the hair cycle - by standard histomorphometric analysis of the back skin hair follicles. In about 40% of old spleens black FM-stainable "debris" could be found under closer histological examination. This study shows that, at least in part, the phenomenon of splenic melanosis in C57BL/6 mice can be correlated with the synchronized skin melanization parallel to the hair cycle progress, and that splenic melanin undergoes gradual degradation during the mouse life.

Ograniczanie wyników

3 Acta Biochimica Polonica

2 Zeszyty Naukowe. Przegląd Hodowlany

3 Plonka P. M.

3 Popik M.

2 Michalczyk D.

2 Salwinski A.

1 Blomstedt L.

1 Handjiski B.

1 Jakubowska M.

1 Kondo K.

1 Michalczyk-Wetula D.

1 Nakamura F.

1 Pak J.

1 Paus R.

1 Slominski A.

1 2013

1 2009

1 2005

2 1996

The changes of proteoglycans during the hair cycle in the mink skin

Fur development in early and late born blue fox [Alopex lagopus]

Splenic aumelanin differs from hair eumelanin in C57BL-6 mice

Splenic melanosis during normal murine C57BL/6 hair cycle and after chemotherapy

Extradermal melanin transfer? Lack of macroscopic spleen melanization in old C57BL-6 mice with de-synchronized hair cycle