ChemDiv shares reviews on Nature and Science Journal articles that impressed us immensely this month. Here is the second part of the July reviews. Today we focus on Drug research, Neurology, Physiology, Microbiology.
Han, Y., Onufer, E.G., Huang, L. et al. Enterically derived high-density lipoprotein restrains liver injury through the portal vein. Science 373, 6553 (2021)
As you know, the human body consists of proteins, fats, carbohydrates, and also of lipoproteins. High-density lipoprotein participates in cholesterol metabolism and may also have anti-inflammatory or anti-microbial roles. Most high-density lipoproteins in the body are synthesized by the liver. The intestine also produces high-density lipoproteins, but its role has not been identified. Using a mouse, the group of scientists traced the fate of high-density lipoproteins synthesized by the intestine. These lipoproteins were directly transported to the liver. Moreover, lipoproteins sequester bacterial lipopolysaccharide from the gut that can trigger liver damage. It can be assumed that high-density lipoproteins may be targetable for the treatment of liver disease.
Brioschi, S., Wang, W., Peng, V. et al. Heterogeneity of meningeal B cells reveals a lymphopoietic niche at the CNS borders. Science 373, 6553 (2021)
Cugurra, A., Mamuladze, T., Rustenhoven, J. et al. Skull and vertebral bone marrow are myeloid cell reservoirs for the meninges and CNS parenchyma. Science 373, 6553 (2021)
The meninges are a three-layer membrane that covers the central nervous system. Brain borders host both innate and adaptive immune cells that mediate immunity of the central nervous system, but little is known about their ontogeny and function. Meningeal immunity is a key component of neuroimmune disorders due to its location. On the pages of “Science”, you can read about two new studies investigating the origin and dynamics of meningeal myeloid cells.
The first group of scientists led by Cugurra found that a large proportion of these myeloid cells are not blood-derived, but rather transit from cranial bone marrow. Moreover, nervous system-derived myeloid cells are less inflammatory and more regulatory than their blood-derived counterparts. The second study of Brioschi reveals that mouse lymphocytes (B-cells) from the meninges preserve immune privilege within the central nervous system, but blood-derived peripheral B-cells may harm the immune system.
Together, these two studies may help in the future treatment of neurological diseases.
Grunewald, M., Kumar, S., Sharife, H. et al. Counteracting age-related VEGF signaling insufficiency promotes healthy aging and extends life span. Science 373, 6554 (2021)
Aging is an established risk factor for vascular diseases, but vascular aging is a high driver of overall organismal aging. On the pages of “Science”, the group of scientists provides evidence for the vascular theory of aging. As you know, all body cells are supplied with oxygen and other blood-borne substances by blood vessels. The vascular system undergoes aging, which leads to progressive functional deterioration, that’s why the vascular theory of aging was put forward. However, experimental support for this proposition is limited. Vascular endothelial growth factor constantly acts to replenish lost vessels and match vascular supply to the tissue needs. Researchers show in aged mice that this factor signaling insufficiency may drive physiological aging across multiple organ systems. Increasing vascular growth factor signaling prevented the age-associated capillary loss, improved organ function, extended life span. Researching the mechanisms of aging may help find a path to healthier aging.
Sato, Y., Atarashi, K., Plichta, D.R. et al. Novel bile acid biosynthetic pathways are enriched in the microbiome of centenarians. Nature (2021)
New research in ‘Nature’ provides another point of view on aging mechanisms. It has been postulated that the microbiome is a key player in determining the health status of aging individuals. It is related to controlling digestive functions, bone density, neuronal activity, immunity, and resistance to pathogen infection. However, centenarians display decreased susceptibility to aging-associated illness. Researchers suggested that there are centenarian-specific members of the gut microbiota which might actively contribute to resistance against environmental stressors, and aimed to identify such beneficial bacteria in the gut microbiota of centenarians. By screening, they identified Odoribacteraceae strains as beneficial ones. Researching beneficial microbiota leads to a new path to the maintenance of intestinal homeostasis and longevity.