Regression of dark color in subterranean fishes involves multiple mechanisms: response to hormones and neurotransmitters

ABSTRACT Organisms with source-populations restricted to the subterranean biotope (troglobites) are excellent models for comparative evolutionary studies, due to their specialization to permanent absence of light. Eye and dark pigment regression are characteristics of most troglobites. In spite of the advance in knowledge on the mechanisms behind eye regression in cave fishes, very little is known about pigmentation changes. Studies were focused on three species of the genus Pimelodella. Exemplars of the troglobitic P. spelaea and P. kronei were compared with the epigean (surface) P. transitoria, putative sister-species of the latter. Melanophore areas and densities are significantly lower in the troglobitic species. Evaluating the in vitro response of these cells to adrenaline, acetylcholine and MCH, we observed a reduced response in both troglobites to adrenaline. The same trend was observed with MCH, but not statistically significant. No response to acetilcholine was detected in all the three. Contrary to expectations, even though eye-regression in P. spelaea was much lower than in P. kronei, pigmentation regression was more advanced. Multiple mechanisms of loss showing a mosaic of traits in troglobitic fishes are discussed here.

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Microstructure and surface texture driven improvement in in-vitro response of laser surface processed AZ31B magnesium alloy

Journal of Magnesium and Alloys ◽

10.1016/j.jma.2020.11.002 ◽

2021 ◽

Author(s):

Tso-Chang Wu ◽

Sameehan S. Joshi ◽

Yee-Hsien Ho ◽

Mangesh V. Pantawane ◽

Subhasis Sinha ◽

...

Keyword(s):

Magnesium Alloy ◽

Surface Texture ◽

Laser Surface ◽

Az31b Magnesium Alloy ◽

In Vitro Response

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Loss of Nitric Oxide Induces Fibrogenic Response in Organotypic 3D Co-Culture of Mammary Epithelia and Fibroblasts—An Indicator for Breast Carcinogenesis

Cancers ◽

10.3390/cancers13112815 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2815

Author(s):

Gang Ren ◽

Xunzhen Zheng ◽

Vandana Sharma ◽

Joshua Letson ◽

Andrea L. Nestor-Kalinoski ◽

...

Keyword(s):

Nitric Oxide ◽

Culture System ◽

Epithelial Mesenchymal Transition ◽

Precancerous Lesions ◽

Three Dimensional ◽

Epidemiological Studies ◽

Mesenchymal Transition ◽

In Vitro Response ◽

Mammary Epithelia

Excessive myofibroblast activation, which leads to dysregulated collagen deposition and the stiffening of the extracellular matrix (ECM), plays pivotal roles in cancer initiation and progression. Cumulative evidence attests to the cancer-causing effects of a number of fibrogenic factors found in the environment, diseases and drugs. While identifying such factors largely depends on epidemiological studies, it would be of great importance to develop a robust in vitro method to demonstrate the causal relationship between fibrosis and cancer. Here, we tested whether our recently developed organotypic three-dimensional (3D) co-culture would be suitable for that purpose. This co-culture system utilizes the discontinuous ECM to separately culture mammary epithelia and fibroblasts in the discrete matrices to model the complexity of the mammary gland. We observed that pharmaceutical deprivation of nitric oxide (NO) in 3D co-cultures induced myofibroblast differentiation of the stroma as well as the occurrence of epithelial–mesenchymal transition (EMT) of the parenchyma. Such in vitro response to NO deprivation was unique to co-cultures and closely mimicked the phenotype of NO-depleted mammary glands exhibiting stromal desmoplasia and precancerous lesions undergoing EMT. These results suggest that this novel 3D co-culture system could be utilized in the deep mechanistic studies of the linkage between fibrosis and cancer.

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