#osteoblast

Gut microbiota that impairs normal skeletal growth identified. Thoughts health innovators?

It is known that the human gut contains trillions of bacteria, known as the microbiota, which play a crucial role in digesting food and regulating the immune system. Gut microbiota also regulates immune processes that influence normal skeletal growth and maturation. However, the influence of specific microbes on immune-based osteoregulation is unknown. Now, a study from researchers at MUSC Health…

Week Seven: Tuesday, February 26, 2019

Reading week was last week and marked the halfway point of the semester and also a slight change in direction of lecture content. Up until now, lectures have been focused on different things that effect biological anthropology but this second half of the semester has switched over to focus more on the different subfields of biological anthropology.

This week we focused in on the subfield of human osteology and paleopathology, basically the study of the human skeleton. We first talked about the osteoblasts, osteoclasts, and osteocytes that make up bone cells and their roles; osteoblasts making new bone and repairing the old, osteoclasts breaking down of old bone, and osteocytes being inactive osteoblasts that are trapped in the bone matrix. We then went on to talk about what exactly bones do aside from hold humans and animals together, this was separated into three subcategories; mechanical, synthesizing and metabolic. Mechanically bones protect organs and allow for tissue attachment, bones also produce red and white blood cells as well as platelets, and they are also where minerals, calcium, and good fats get stored.

Honey, I’m Bone

With the potential to transform into brand new healthy tissue, stem cells offer the promise of repair and recovery to millions of people worldwide. These adipose-derived mesenchymal stem cells (ADMSCs, green) are multipotent – they can change, or differentiate, into several types of cell, like fat, bone or cartilage. The question is how to encourage one destiny over the others? Here ADMSCs are growing on 'scaffolds' made from nanofibers arranged in different ways – randomly (left), in one direction (middle), or in a honeycomb pattern (right). Pictured one (top), two (middle) or six (bottom) days after sticking to their scaffolds, the stem cells grow and stretch into different shapes – the cells on the right curve themselves around the honeycomb. It turns out this arrangement is just the thing to encourage differentiation into osteoblasts [new bone cells], and could influence future designs in bone tissue engineering.

Written by John Ankers

Image from work by Salima Nedjari, Firas Awaja and George Altankov

Institute for Bioengineering of Catalonia (IBEC), Barcelona, Spain

Image originally published under a Creative Commons Licence (BY 4.0)

Published in Scientific Reports, November 2017

Growing Stripes

In humans, healing broken bones is slow and painful, and lost limbs can never be regrown, yet some species have far more resilient skeletons. Zebrafish are able to entirely regenerate amputated fins, an impressive feat completed within only two weeks. Clusters of specialised skin cells split and move from the base to the tip of the fin to activate bone-producing stem cells, or osteoblasts, using a signalling molecule known as sonic hedgehog (Shh). Labelling the cells responding to Shh with green fluorescence in a developing tail fin (pictured) tracks the growing fin bones, or rays. Communication between skin cells and osteoblasts is critical to obtaining a skeleton with the appropriate pattern: when the Shh signalling pathway is blocked, fins develop incorrectly, with straight, unbranched rays. While not aiming to replicate the regenerative capacity of zebrafish in humans, understanding how Shh underpins it could inspire new ways to stimulate bone repair.

Written by Emmanuelle Briolat

Image courtesy of Kryn Stankunas

Institute of Molecular Biology, University of Oregon, Eugene, OR, USA

Research published in Development, March 2017

Space Marine

As the old joke goes: three fish are in a tank, one says “How do you drive this thing?” Medaka fish like these have gone one better – blasting off on a space rocket. On board the International Space Station (ISS), medaka make good models for the effects of low gravity on humans. Recently, scientists in Japan watched remotely from Earth as a microscope on the ISS took a close look at developing medaka bone cells. Within a day of being in microgravity, genes in the fish’s osteoblast and osteoclast cells, which help to make new bones, began to change. This strange bone-building response may combat the loss bone minerals brought on by low gravity, suggesting clues to why human astronauts often have skeletal problems. Future space-travellers may have these pioneering gravitational biology experiments, and the medaka fish, to thank for pain-free missions in the future.

Written by John Ankers

Image courtesy of Professor Kiyoshi Naruse, National Institute for Basic Biology, Aichi, Japan

Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan

Image copyright held by the photographer

Research published in Scientific Reports, December 2016

The Scientific Research Notes of S. Sunkavally, Printed Part, Page.256.